Yaskawa iQPump1000 Drive Fault Codes

Complete guide to Yaskawa iQPump1000 drive fault codes. Learn to troubleshoot Loss of Prime, Low Water alarms, Transducer errors, and access real-time fault logs.

iQPump1000 Fault Codes Reference Table

Below is the complete reference list of faults and alarms. The iQPump1000 display shows the code (e.g., LPo) and a scrolling text description (e.g., “Loss of Prime”), reducing the need to memorize abbreviations.

iQPump1000 Fault Codes Reference Table

Fault Code and Meaning	Cause and Remedy
ACCUM Accumulated Level Fault	Cause: The accumulated level has exceeded the values set in P6-11 to P6-14. This is only effective when P6-15 (Accumulated Behavior) is set to 2 or 3. Remedy: Set the Accumulated Level fault characteristics in P6-11 to P6-14 and P6-16. Drive response to this condition is controlled by P6-15. Auto-restart of this fault is controlled by P6-15 and P6-05 (Flow Accumulation Reset).
AJF Anti-Jam Fault	Cause: The drive was not able to clear debris from the impeller in fewer than the number of attempts set in P7-02. Remedy: Check for proper pump operation. Remove debris from the pump impeller. Set the Anti-jam fault characteristics in P7-02 to P7-08. Drive response to this condition is controlled by P7-01.
AUXFB PI Aux Lvl Loss (Wire-break detection)	Cause: The analog input programmed for "PI Aux FB Level" (H3-xx = 27) has dropped below 3 mA or risen above 21 mA for longer than 1 second. Remedy: Repair transducer or wiring.
bAT Digital Operator Battery Voltage Low	Cause: The digital operator battery is low. Remedy: Replace the digital operator battery.
boL Braking Transistor Overload Fault	Cause: The wrong braking resistor is installed. Remedy: Select the correct braking resistor.
bUS Option Communication Error	Cause: No signal was received from the PLC, faulty communications wiring, or communication data error due to noise. Remedy: Check for faulty wiring. Correct the wiring. Check for disconnected cables and short circuits and repair as needed. Check options to minimize noise (counteract noise in control/main circuit, ground wiring). Use surge absorbers on other equipment (switches/relays). Use shielded lines and ground correctly. Install EMC noise filter to drive power supply input. Replace option card if wiring is fine but error persists.
CE MEMOBUS/Modbus Communication Error	Cause: Control data was not received for the CE detection time set to H5-09. Faulty wiring or noise interference. Remedy: Check for faulty wiring or disconnected cables. Check various options to minimize noise effects. Counteract noise in control circuit, main circuit, and ground wiring. Use recommended cables/shielded lines and ground the shield properly. Ensure other equipment (switches/relays) are not causing noise; use surge suppressors. Install EMC noise filter to the drive power supply input.
CPF11 to CPF14 CPF16 to CPF19 Control Circuit Error	Cause: There is a self-diagnostic error in the control circuit. Remedy: Cycle power to the drive. If problem continues, replace the control board or entire drive.
CPF02 A/D Conversion Error	Cause: Control circuit is damaged (A/D conversion error or control circuit error). Remedy: Cycle power to the drive. If problem continues, replace the control board or entire drive.
CPF03 Control Board Connection Error	Cause: Connection error between the control board and the drive. Remedy: Turn off power and check the connection between the control board and the drive. If problem continues, replace the control board or entire drive.
CPF06 EEPROM Memory Data Error	Cause: Error in EEPROM control circuit, or power supply was switched off while parameters were being saved. Remedy: Turn off power and check connection between control board and drive. Reinitialize the drive (A1-03 = 2220, 3330). If problem continues, replace control board or entire drive.
CPF07 or CPF08 Terminal Board Connection Error	Cause: Faulty connection between terminal board and control board. Remedy: Turn off power and reconnect the terminal board. If problem continues, replace control board or entire drive.
CPF20 or CPF21 Control Circuit Error	Cause: Hardware is damaged. Remedy: Cycle power to the drive. If problem continues, replace control board or entire drive.
CPF22 Hybrid IC Failure	Cause: Hybrid IC failure on the power board. Remedy: Cycle power to the drive. If problem continues, replace power board or entire drive.
CPF23 Control Board Connection Error	Cause: Hardware is damaged (connection error between control board and drive). Remedy: Turn off power and check connection between control board and drive. If problem continues, replace control board or entire drive.
CPF24 Drive Unit Signal Fault	Cause: Hardware is damaged (drive capacity cannot be detected). Remedy: If problem continues, replace control board or entire drive.
CPF25 Terminal Board Not Connected	Cause: Terminal board is not connected correctly. Remedy: Reconnect the terminal board to the connector on the drive, then cycle power.
CPF26 to CPF35 CPF40 to CPF43 Control Circuit/CPU Error	Cause: Hardware is damaged. Remedy: If problem continues, replace control board or entire drive.
DIFF Differential Feedback Detected	Cause: The difference between PID Feedback and Differential Feedback (H3-xx = 28) exceeded P4-18 level for time set in P4-19. Remedy: Replace the feedback transducer or transducers. Verify parameter settings P4-18 to P4-20.
E5 SI-T3 Watchdog Timer Error	Cause: The watchdog timed out. Data has not been received from the PLC. Remedy: Execute DISCONNECT or ALM_CLR, then issue CONNECT or SYNC_SET command. Refer to SI-T3 Option Technical Manual for troubleshooting.
EF0 Option Card External Fault	Cause: External fault received from PLC (F6-03 not equal to 3), or problem with PLC program. Remedy: Remove the cause of the external fault. Remove the external fault input from the PLC. Check the PLC program and correct problems.
EF1 to EF8 Pump Fault (Input Terminals S1-S8)	Cause: An external device tripped an alarm function (Wiring incorrect, Multi-function contact input setting incorrect). Remedy: Remove the cause of the external fault and reset the fault. Properly connect signal lines to terminals assigned for external fault detection (H1-xx = 20 to 2B). Reconnect signal line. Check for unused terminals set for H1-xx = 20 to 2B. Change terminal settings.
Err EEPROM Write Error	Cause: Noise corrupted data while writing to EEPROM, or hardware problem. Remedy: Press "ENTER" on the digital operator. Correct the parameter setting. Cycle power to the drive. If problem continues, replace control board or entire drive.
FAn Internal Fan Fault	Cause: Internal cooling fan malfunctioned, or fault detected in fan/magnetic contactor to power supply. Remedy: Cycle power to the drive. Check for fan operation. Verify cumulative operation time (U4-03) and maintenance timer (U4-04). Replace fan if life exceeded or damaged. If fault continues, replace power board/gate drive board or entire drive.
FDBKL PID Feedback Loss (Wire Break)	Cause: The analog input programmed for PID feedback has risen above 21 mA or fallen below 3 mA. Remedy: Confirm that the PID feedback source is installed and working properly. Drive response is controlled by b5-12 and b5-13. Auto-restart is controlled by L5-42.
Flow Rate Limit Drive output speed limited	Cause: Excessive or insufficient Flow. Drive output speed is being limited due to Flow Rate (U1-83). Remedy: If Flow Rate Limiter is activating improperly, confirm parameter settings P6-01, P6-26, P6-27, P6-28, and P6-29.
GF Ground Fault	Cause: Motor insulation damaged, damaged motor cable creating short circuit, excessive leakage current, or hardware problem. Remedy: Check insulation resistance of the motor. Replace the motor. Check motor cable for short circuits or damage; replace if needed. Reduce carrier frequency. Set b3-01 to 1 to enable Speed Search at Start. If problem continues, replace control board or entire drive.
HFB High Feedback	Cause: The feedback signal has risen above the level set in P1-11 for the time set in P1-12. Remedy: Set the High Feedback fault characteristics in P1-11 and P1-12. Drive response controlled by P1-13. Auto-restart controlled by L5-41.
HIAUX High PI Auxiliary Feedback Level	Cause: PI Aux Feedback has risen above Q6-12 level for longer than time set in Q6-13. Remedy: Lower the PI Aux Feedback level. Adjust parameters Q6-12 and Q6-13.
HIFLO High Flow	Cause: The flow is too high. Measured water flow risen above P6-17 level for time set in P6-18. Remedy: Reduce the flow. Set High Flow fault characteristics in P6-17 and P6-18. Drive response controlled by P6-19. Auto-restart controlled by P6-19.
HISUC High Section Pressure	Cause: Suction pressure has risen above Q5-12 level for longer than time set in Q5-13. Remedy: Reduce the system pressure. Set High Suction Pressure fault characteristics in Q5-12, Q5-13, and Q5-18. Drive response controlled by Q5-14. Auto-restart controlled by Q5-14.
HWL High Water Level	Cause: Low Water Level switch activated or P1-31 (High Water Digital Input) programmed incorrectly. Remedy: Lower the water level and/or adjust the High Water Level switch.
LF Output Phase Loss	Cause: The output cable is disconnected. Remedy: Check for wiring errors and properly connect the output cable. Correct the wiring. Cause: The motor winding is damaged. Remedy: Check the resistance between motor lines. Replace the motor if the winding is damaged. Cause: The output terminal is loose. Remedy: Apply the tightening torque specified in the manual to fasten the terminals. Cause: The rated current of the motor being used is less than 5% of the drive rated current. Remedy: Check the drive and motor capacities. Cause: An output transistor is damaged. Remedy: If the problem continues, replace the control board or the entire drive. Contact Yaskawa. Cause: A single-phase motor is being used. Remedy: The drive cannot operate a single phase motor.
LF3 Power Unit Output Phase Loss 3	Cause: The gate drive board in the power unit is damaged. Remedy: Cycle the power supply. If the fault continues to occur, replace the gate drive board or the drive. Cause: Cable to the current detection circuit in the power unit is damaged or not connected properly. Remedy: Check for incorrect wiring and correct any wiring mistakes. Cause: Cable between the output reactor and the power unit is loose or not connected. Remedy: Contact Yaskawa or your nearest sales representative for instructions.
LFB Low Feedback	Cause: The feedback signal has dropped below the level set in P1-08 for the time set in P1-09. Remedy: Set the Low Feedback fault characteristics in P1-08 and P1-09. Drive response to this condition is controlled by P1-10. Auto-restart of this fault is controlled by L5-40.
LOAUX Low PI Auxiliary Feedback Level	Cause: PI Aux Feedback has fallen below the Q6-09 level for longer than the time set in Q6-10. Remedy: Raise the PI Aux Feedback level. Adjust parameters Q6-09 and Q6-10.
LOP Loss of Prime	Cause: The pump load (output current, kilowatts, or power) has dropped below the level set in P1-19 for the time set in P1-20. Remedy: Check for a dry well, air in the system, or no water in the system. Restart the pump using the preferred priming method. Set the Loss of Prime fault characteristics in P1-18, P1-19, P1-20, and P1-21. Drive response to this condition is controlled by P1-21. Auto-restart of this fault is controlled by L5-51 and P1-23.
LOSUC Low Suction Pressure	Cause: The suction pressure has fallen below the level set in Q5-09 for longer than the time set in Q5-10. Remedy: Increase the system pressure. Set the Low Suction fault characteristics in Q5-09, Q5-10, and Q5-18. Drive response is controlled by Q5-11. Auto-restart is controlled by Q5-11 and Q5-15.
LOWFL Low Flow	Cause: Insufficient flow. Measured water flow has fallen below P6-06 level for time set in P6-07. Remedy: Increase flow. Set the Low Flow fault characteristics in P6-06, P6-07, and P6-08. Drive response is controlled by P6-09. Auto-restart is controlled by P6-09 and P6-10.
LOWWL Low Water Level	Cause: The water level has fallen below the level set in Q4-09 for the longer than the time set in Q4-10. Remedy: Raise the water level. Set the Low Water Level fault characteristics in Q4-09 and Q4-10. Drive response is controlled by Q4-11. Auto-restart is controlled by Q4-11 and Q4-12.
LWL Low Water Level (Digital Input)	Cause: The Low Water Level switch is activated, defective, or P1-30 is programmed incorrectly. Remedy: Raise the water level and/or adjust the Low Water Level switch.
MSL Net Master Lost	Cause: The MEMOBUS master has been lost. Network Recovery is set to Fault MSL and no message received within time P9-26. Remedy: Increase the P9-26 setting to account for network latency. Verify that there is a drive on the network with parameter P1-01 set to 3 and P9-27 to 0. Check network connections and verify H5-01 and P9-25 settings for all drives.
NMS Not Maintaining Setpoint	Cause: When the feedback deviates from the setpoint at a level greater than P1-15, for a time set in P1-16. Remedy: Check for a blocked impeller, over cycling, or broken pipe. Set the Not Maintaining Setpoint fault characteristics in P1-16 and P1-17. Drive response is controlled by P1-17. Auto-restart is controlled by L5-50.
nSE Node Setup Error	Cause: A terminal assigned to the node setup function closed during run, or Run command issued while setup active. Remedy: Stop the drive when using the node setup function.
oC Overcurrent	Cause: The motor has been damaged due to overheating or the motor insulation is damaged. Remedy: Check the insulation resistance. Replace the motor. Cause: One of the motor cables has shorted out or there is a grounding problem. Remedy: Check the motor cables. Remove the short circuit and reapply power to the drive. Check the resistance between the motor cables and the ground terminal. Replace damaged cables. Cause: The load is too heavy. Remedy: Measure the current flowing into the motor. Replace the drive with a larger capacity drive if current exceeds rated current. Reduce the load to avoid sudden changes. Cause: The acceleration or deceleration times are too short. Remedy: Increase the acceleration time (C1-01, C1-03). Increase the S-curve characteristics (C2-01 through C2-04). Increase the capacity of the drive. Cause: The drive is attempting to operate a specialized motor or a motor larger than the maximum size allowed. Remedy: Check the motor capacity. Ensure that the rated capacity of the drive is greater than or equal to the motor nameplate. Cause: Magnetic contactor (MC) on the output side of the drive has turned on or off. Remedy: Set up the operation sequence so the MC does not trip while the drive is outputting current. Cause: V/f setting is not operating as expected. Remedy: Check the ratios between the voltage and frequency. Set parameters E1-04 through E1-10 appropriately. Cause: Excessive torque compensation. Remedy: Check the amount of torque compensation. Reduce the torque compensation gain (C4-01). Cause: Drive fails to operate properly due to noise interference. Remedy: Review possible solutions for handling noise interference. Check control circuit lines, main circuit lines, and ground wiring. Cause: Overexcitation gain is set too high. Remedy: Check if the fault occurs simultaneously with overexcitation function operation. Reduce the value of n3-13 (Overexcitation Deceleration Gain). Cause: Run command was applied while motor was coasting. Remedy: Set b3-01 to 1 to enable Speed Search at Start. Cause: The rated output current of the drive is too small. Remedy: Use a larger drive.
oFA00 Option Card Connection Error at Option Port CN5-A Option compatibility error	Cause: The option card installed into port CN5-A is incompatible with the drive. Remedy: Check if the drive supports the option card to be installed. Contact Yaskawa for assistance.
oFA01 Option Card Fault at Option Port CN5-A Option not properly connected	Cause: The option card connection to port CN5-A is faulty. Remedy: Turn off the power and reconnect the option card. Check if the option card is properly plugged into the option port. Make sure the card is fixed properly. If the option is not a communication option card, try to use the card in a different option port. If the card works in a different port, CN5-A is damaged (replace drive). If the error persists (oFb01 or oFC01 occur), replace the option card.
oFA03 to oFA06 oFA10, oFA11 oFA12 to oFA17 oFA30 to oFA43 Option Card Error Occurred at Option Port CN5-A	Cause: Option card or hardware is damaged. Remedy: Cycle power to the drive. If the problem continues, replace the control board or the entire drive. Contact Yaskawa for instructions on replacing the control board.
oFb00 Option Card Fault at Option Port CN5-B Option compatibility error	Cause: The option card installed into port CN5-B is incompatible, or a communication option card has been installed in port CN5-B. Remedy: Make sure the drive supports the option card to be installed. Communication option cards are only supported by option port CN5-A. Move the card to CN5-A.
oFb01 Option Card Fault at Option Port CN5-B Option not properly connected	Cause: The option card connection to port CN5-B is faulty. Remedy: Turn off the power and reconnect the option card. Check if the option card is properly plugged in and fixed. Try to use the card in a different option port. If it works there, CN5-B is damaged (replace drive). If the error persists, replace the option card.
oFb02 Option Card Fault at Option Port CN5-B Same type of option card is currently connected	Cause: An option card of the same type is already installed in option port CN5-A. Remedy: Only one of each option card type can be installed simultaneously. Make sure only one type of option card is connected. If an input option card is in CN5-A, install a communication, digital input, or analog input option instead.
oFb03 to oFb11 oFb12 to oFb17 Option Card error occurred at Option Port CN5-B	Cause: Option card or hardware is damaged. Remedy: Cycle power to the drive. If the problem continues, replace the control board or the entire drive.
oFC00 Option Card Connection Error at Option Port CN5-C Option compatibility error	Cause: The option card installed into port CN5-C is incompatible, or a communication card is installed in CN5-C. Remedy: Confirm that the drive supports the option card. Communication option cards are only supported by option port CN5-A.
oFC01 Option Card Fault at Option Port CN5-C Option not properly connected	Cause: The option card connection to port CN5-C is faulty. Remedy: Turn the power off and reconnect the option card. Check if the option card is properly plugged in and fixed. Try to use the card in a different option port. If it works there, CN5-C is damaged (replace drive). If the error persists, replace the option card.
oFC02 Option Card Fault at Option Port CN5-C Same type of option card is currently connected	Cause: An option card of the same type is already installed in option port CN5-A or CN5-B. Remedy: Only one of each option card type can be installed simultaneously. Make sure only one type of option card is connected.
oFC03 to oFC11 oFC12 to oFC17 Option Card Error Occurred at Option Port CN5-C	Cause: Option card or hardware is damaged. Remedy: Cycle power to the drive. If the problem continues, replace the control board or the entire drive.
oFC50 to oFC55 Option Card Error Occurred at Option Port CN5-C	Cause: Option card or hardware is damaged. Remedy: Refer to the option manual for details.
oH Heatsink Overheat Temperature exceeded pre-alarm level (L8-02)	Cause: Surrounding temperature is too high or Load is too heavy. Remedy: Check the temperature surrounding the drive. Verify it is within specifications. Improve air circulation within the enclosure panel. Install a fan or air conditioner to cool the area. Remove anything near the drive producing excessive heat. Measure output current and decrease the load. Lower the carrier frequency (C6-02).
Internal Fan Fault Internal cooling fan is stopped	Cause: Fan failure or obstruction. Remedy: Replace the cooling fan. After replacing, set parameter o4-03 to 0 to reset cooling fan maintenance.
oH1 Overheat 1 (Heatsink Overheat) Temperature exceeded drive overheat level	Cause: Surrounding temperature is too high or Load is too heavy. Remedy: Check temperature surrounding the drive. Improve air circulation; install fan or AC. Remove heat sources near the drive. Measure output current. Lower the carrier frequency (C6-02). Reduce the load.
oH4 Motor Overheat Fault (PTC Input)	Cause: Motor has overheated. Remedy: Check the size of the load, accel/decel times, and cycle times. Decrease the load. Increase acceleration and deceleration times (C1-01 through C1-04). Adjust the preset V/f pattern (E1-04 to E1-10) by reducing E1-08 and E1-10 (do not set too low). Check the motor rated current and enter into E2-01. Ensure motor cooling system is operating normally.
oH5 Motor Overheat (NTC Input)	Cause: Motor has overheated. Remedy: Reduce the load. Check the ambient temperature.
oL1 Motor Overload Electronic motor overload protection tripped	Cause: Load is too heavy; Cycle times too short; Low speed operation with high load; Output voltage too high; Wrong motor rated current set; Base frequency incorrect. Remedy: Reduce the load. Increase acceleration and deceleration times (C1-01 through C1-04). If operating at low speeds, increase motor capacity or use a specific motor. Adjust user-set V/f pattern (reduce E1-08 and E1-10). Check motor-rated current and update E2-01. Check rated frequency on nameplate and update E1-06.
oL1 (cont) Motor Overload (Additional Causes)	Cause: Electrical thermal protection mismatch; Relay operating at wrong level; Overexcitation; Speed Search parameters; Power supply loss. Remedy: Check motor characteristics and correct L1-01 setting. Install external thermal relay if needed. Prevent excessive overexcitation or apply cooling; reduce excitation deceleration gain (n3-13). Set L3-04 to a value other than 4. Adjust Speed Search current (b3-02) and deceleration time (b3-03). Check power supply for phase loss.
oL2 Drive Overload Thermal sensor triggered overload protection	Cause: Load too heavy; Accel/decel too short; Output voltage too high; Drive capacity too small; Low speed overload; Excessive torque compensation; Speed search errors; Phase loss. Remedy: Reduce the load. Increase acceleration and deceleration times (C1-01 through C1-04). Adjust V/f pattern (reduce E1-08 and E1-10). Replace the drive with a larger model. Lower the carrier frequency (C6-02). Reduce torque compensation gain (C4-01). Adjust Speed Search parameters (b3-03, b3-02). Check power supply for phase loss.
oL3 Overtorque Detection 1	Cause: Parameter settings not appropriate for load; Fault on machine side (locked up). Remedy: Check L6-02 and L6-03 settings. Check the status of the load. Remove the cause of the fault.
oL4 Overtorque Detection 2	Cause: Parameter settings are not appropriate for the load. Remedy: Check the settings of parameters L6-05 and L6-06.
oL7 High Slip Braking oL	Cause: Output frequency stayed constant longer than time set in n3-04; Excessive load inertia; Motor driven by load; Braking restriction. Remedy: Reduce deceleration times (C1-02, C1-04) if not using High Slip Braking. Use a braking resistor to shorten deceleration time. Increase parameter n3-04 (High-slip Braking Overload Time). Install a thermal relay and increase n3-04 to maximum.
oPr External HOA Keypad Connection Fault	Cause: HOA keypad is not properly connected to the drive. Remedy: Check the connection between the keypad and the drive. Replace the cable if damaged. Turn off drive power, disconnect keypad, reconnect, and reapply power.
ov Overvoltage DC bus voltage exceeded level	Cause: Decel time too short; Fast accel causing overshoot; Excessive braking load; Surge voltage; Ground fault; Speed Search parameters; Input voltage too high; Wiring errors; Noise interference. Remedy: Increase deceleration time (C1-02, C1-04). Install dynamic braking resistor or unit. Enable Stall Prevention (L3-04 = 1). Increase acceleration time or use S-curve (L3-11 = 1). Install a DC link choke for power surges. Check motor wiring for ground faults. Adjust Speed Search current (b3-02) and decel time (b3-03). Check input voltage. Check braking transistor/resistor wiring. Review noise interference solutions and grounding.
PF Input Phase Loss	Cause: Drive input power has an open phase or has a large imbalance of voltage between phases. Detected when L8-05 is set 1 (enabled). Remedy: Check for wiring errors in the main circuit drive input power. Correct the wiring. Ensure the terminals are tightened properly. Apply tightening torque as specified (Page 110). Check the voltage from the drive input power. Stabilize drive input power or disable phase loss detection. Check the maintenance time for the capacitors (U4-05). Replace if > 90%. If power appears normal but alarm continues, replace the control board or entire drive.
PoC Pump Over Cycle	Cause: The pump has exceeded the number of cycles set in P2-10 in the time set in P2-11 and P2-12 is set to 2 (fault). Remedy: Set the Pump Over Cycle fault characteristics in P2-10 and P2-11. Check Drive response setting in P2-12 (Over Cycling Mode). Check Auto-restart settings in L5-52. Set automatic setpoint compensation in P2-12, P2-13, and P2-14.
rF Braking Resistor Fault	Cause: The resistance of the braking resistor is too low. Remedy: Select a braking resistor option that fits the drive braking transistor specification. If a regenerative converter or unit is used, set L8-55 to 0.
rH Braking Resistor Overheat	Cause: Braking resistor protection was triggered. Fault detection enabled when L8-01 = 1. Remedy: Check the load, deceleration time, and speed. Reduce the load inertia. Increase the deceleration times (C1-01 to C1-04). Replace the dynamic braking option with a larger device. Check the duty cycle (Max 3% when L8-01 = 1).
rr Dynamic Braking Transistor	Cause: The built-in dynamic braking transistor failed. Remedy: Cycle power to the drive and check for reoccurrence of the fault. Replace either the control board or the entire drive.
SC IGBT Short Circuit or Ground Fault	Cause: IGBT fault or short circuit detection circuit fault. Remedy: Check motor wiring. Turn off power supply, then turn it on. If problem continues, contact Yaskawa. Check drive output side short circuit (B1, U/T1, V/T2, W/T3).
SEr Too Many Speed Search Restarts	Cause: The number of Speed Search restarts exceeded the value set to b3-19. Remedy: Reduce the detection compensation gain during Speed Search (b3-10). Increase the current level when attempting Speed Search (b3-17). Increase the detection time during Speed Search (b3-18). Repeat Auto-Tuning. Set b3-14 to 1 to enable Bi-Directional Speed Search.
SPL Suction Pressure Loss	Cause: Wire-break detection for suction pressure. Analog input dropped below 3 mA or rose above 21 mA for longer than 1 second. Remedy: Repair pressure sensor or wiring.
TdE Time Data Error	Cause: An error has occurred in the Real-Clock Time function of the HOA keypad. Remedy: Replace the HOA keypad.
THo Thermistor Disconnect	Cause: The thermistor that detects motor temperature has become disconnected. Remedy: Check the thermistor wiring.
TIE Time Interval Error	Cause: An error has occurred in the Real-Clock Time function of the HOA keypad. Remedy: Replace the HOA keypad.
TIM Time Not Set	Cause: The Real-Time Clock is not set in parameter o4-17 (first power up or battery low). Remedy: Set o4-17 to 1 to set the time for the HOA keypad. Cycle power to the drive and set the Real Time Clock within 30 seconds. Replace the HOA keypad battery and set the Real-Time Clock. If error persists, replace the digital operator.
TLGI Geothermal Input	Cause: Temperature Lost Geothermal Input. Input signal level dropped below 3mA or rose above 21mA. Remedy: Confirm that the device connected to the analog input terminal is installed and working properly. Assign one of the analog inputs to “Geothermal Temperature” (H3-0x = 21).
UL3 Undertorque Detection 1	Cause: Current has fallen below minimum value (L6-02) for longer than allowable time (L6-03). Remedy: Check the settings of parameters L6-02 and L6-03. Check the load for any problems (e.g. broken belt/coupling).
UL4 Undertorque Detection 2	Cause: Current has fallen below minimum value (L6-05) for longer than allowable time (L6-06). Remedy: Check L6-05 and L6-06 settings. Check the load for any problems.
UL6 Motor Underload	Cause: The load has fallen below the underload curve defined in L6-14. Remedy: Adjust the value set to L6-14 so that output current remains above the motor underload curve during normal operation.
UnbC Current Unbalance	Cause: The internal current sensor has detected a current unbalance situation. Remedy: Check wiring. Check for damaged transistors. Check for short circuits or grounding problems on the connected motor.
Uv1 DC Bus Undervoltage	Cause: DC bus voltage fell below detection level (L2-05). Input power phase loss or loose wiring. Remedy: Check main circuit drive input power wiring. Ensure no loose terminals; tighten to torque specs. Check voltage is within range. Check magnetic contactor. Check capacitor maintenance time (U4-05). Check the relay or contactor on the soft-charge bypass circuit.
Uv2 Control Power Supply Voltage Fault	Cause: Voltage is too low for the control drive input power. Remedy: Correct the setting to L2-02 or install an optional Momentary Power Loss Ride-Thru unit. Cycle power to the drive. Check if fault reoccurs. If problem continues, replace control board or power supply.
Uv3 Undervoltage 3 (Soft-Charge Bypass)	Cause: The soft-charge bypass circuit failed (relay or contactor damaged). Remedy: Cycle power to the drive and see if fault reoccurs. Check monitor U4-06 for performance life of soft-charge bypass. Replace control board or entire drive if U4-06 > 90% or fault persists.
Uv4 Gate Drive Board Undervoltage	Cause: Voltage drop in the gate drive board circuit. Remedy: Cycle power to the drive and see if fault reoccurs. If problem continues, replace the gate drive board or the entire drive.
VLTS Volute-Thermostat Fault	Cause: Digital input assigned to volute/thermostat (H1-xx = 88/89) is active. Remedy: Check the wiring or wait for the volute or motor to cool. Program only one digital input to either 88 or 89. Check auto-restart parameter L5-53.
voF Output Voltage Detection Fault	Cause: Hardware damaged or internal drive module overheat due to abnormal ambient power. Remedy: Lower ambient temperature. Replace the control board or the entire drive.
WLL Water Level Loss	Cause: Analog input for "WaterLvl/Suction" dropped below 3mA or rose above 21mA. Remedy: Repair level sensor or wiring.
ACCUM Accumulated Level Error	Cause: The accumulated level has exceeded the values set in P6-11 to P6-14. This is only effective when P6-15 (Accumulated Behavior) is set to 1 (alarm). Remedy: Set the Accumulated Level fault characteristics in P6-11 to P6-14 and P6-16. Check drive response in P6-15. Auto-restart is controlled by P6-15 and P6-05 (Flow Accumulation Reset).
Accum Lvl Reached Flow Accumulation level reached	Cause: Accum Behavior P6-15 is set to 5 (Stop, Alarm, & Reset) and the Accumulated Level has been reached. Remedy: Cycle the Run command.
AnalogFB Lost Analog Feedback Lost	Cause: Defective or broken analog input source. Analog feedback not detected. Remedy: Confirm that the PI feedback source is installed and working properly. If there is no feedback source, set P9-02 to 3 (read network PI feedback). Set H3-0x to B if the analog input source is to be used for PI feedback.
Anti-Jam Active Anti-Jam Alarm	Cause: The drive was not able to clear debris from the impeller in fewer than the attempts set in P7-02. Remedy: Check for proper pump operation. Set the Anti-jam fault characteristics in P7-02 to P7-08. Check P7-01 (Anti-jam Operation Selection).
AUXFB PI Aux Lvl Loss	Cause: The analog input programmed for "PI Aux FB Level" (H3-xx = 27) has dropped below 3 mA or risen above 21 mA for longer than 1 second. Remedy: Repair transducer or wiring.
Backup FdBk Lost Backup Feedback Device lost	Cause: Wire-break on Analog Input Terminal programmed for Backup PI Feedback (H3-xx = 24). Backup PI Feedback Transducer is broken. Remedy: Check the connection of the Backup Feedback transducer. Replace Backup PI Feedback Transducer.
bAT Digital Operator Battery Voltage Low	Cause: The digital operator battery is low. Remedy: Replace the digital operator battery.
bb Baseblock	Cause: External baseblock signal was entered via one of the multi-function input terminals (S1 to S8). Remedy: Check external sequence and baseblock signal input timing.
boL Braking Transistor Overload Fault	Cause: The proper braking resistor has not been installed. Remedy: Select the proper braking resistor.
bUS Option Communication Error	Cause: Connection is broken, master controller stopped communicating, or option is damaged. Data error due to noise. Remedy: Check for faulty wiring or short circuits. Repair as needed. If wiring is fine but fault persists, replace the option. Check connector pins alignment; reinstall option. Take steps to counteract noise (ground wiring, surge absorbers, shielded lines). Install an EMC noise filter to the drive input power.
CALL Serial Communication Transmission Error	Cause: Communications wiring is faulty/shorted, programming error on master side, or communications circuitry is damaged. Remedy: Check for wiring errors, disconnected cables, and short circuits. Check communications at start-up and correct programming errors. Perform a self-diagnostics check. If problem continues, replace control board or entire drive.
CE MEMOBUS/Modbus Communication Error	Cause: Data error due to noise, incompatible protocol, CE detection time (H5-09) too short, or cable disconnected/damaged. Remedy: Minimize noise effects (shielded lines, grounding, EMC filter). Check H5 parameter settings and protocol compatibility. Set a longer CE detection time using parameter H5-09. Check the PLC software settings. Check connector signals; replace communications cable.
CE - Comm Loss Drive runs at H5-14	Cause: MEMOBUS/Modbus Communicator Error (Drive continues running based on H5-14 setting). Data error due to noise or cable issues. Remedy: Check options available to minimize noise. Check H5 parameter settings. Check PLC settings and connection. Replace communications cable if damaged.
Current Limit Foldback Current Limit Foldback	Cause: Drive output speed is being limited due to the output current limit. Remedy: Reduce the load. Verify setting of Q3-02. Change to a larger drive size.
De-Scale/De-rag Active De-scale is running	Cause: De-scale is programmed and enough run-time has been accumulated. Remedy: If De-scale/De-rag is not desired, program P8-01 = 0 (Disabled). Adjust the De-scale Run Timer P8-08.
Differential FB Detected Differential Feedback Detected	Cause: The difference between the PID Feedback and the Differential Feedback (H3-xx = 28) exceeded the P4-18 level for the time set in P4-19. Remedy: Replace the feedback transducer or transducers. Verify parameter settings P4-18 to P4-20.
dnE Drive Disabled	Cause: "Drive Enable" is set to a multi-function contact input (H1-xx = 6A) and the contact is open. Remedy: Check the operation sequence.
EF Forward/Reverse Run Command Input Error	Cause: Sequence error. Both forward run and reverse run closed simultaneously for longer than 0.5 s. Remedy: Check the forward and reverse command sequence and correct the problem. Note: When minor fault EF detected, motor ramps to stop.
EF0 Option Card External Fault	Cause: An external fault was received from the PLC (F6-03 set to 3) or PLC program problem. Remedy: Remove the cause of the external fault. Remove the external fault input from the PLC. Check the PLC program and correct problems.
EF1 - EF8 Pump Fault / External Fault (Terminals S1-S8)	Cause: External fault at multi-function input terminal (S1 through S8). An external device has tripped an alarm function. Wiring is incorrect. Remedy: Remove the cause of the external fault and reset the multi-function input value. Ensure signal lines are connected properly to terminals assigned for external fault detection (H1-xx = 2C to 2F). Reconnect the signal line. Check if unused terminals have been set for External Fault improperly.
EoF Emergency Override Forward Run	Cause: The multi-function digital input for EmergOverrideFWD (H1-xx = AF) has been closed. Remedy: Open H1-xx = AF if the emergency condition is no longer present.
Eor Emergency Override Reverse Run	Cause: The multi-function digital input for EmergOverrideREV (H1-xx = B0) has been closed. Remedy: Open H1-xx = B0 if the emergency condition is no longer present.
E5 SI-T3 Watchdog Timer Error	Cause: The watchdog timed out. Data has not been received from the PLC. Remedy: Execute DISCONNECT or ALM_CLR, then issue a CONNECT or SYNC_SET command. Refer to the SI-T3 Option Technical Manual.
FAn Internal Fan Error	Cause: Internal cooling fan has malfunctioned or magnetic contactor failure. Remedy: Cycle power to the drive. Check for fan operation. Verify cumulative operation time (U4-03) vs maintenance timer (U4-04). If fan is damaged/expired, follow replacement instructions. If fault continues, replace power board/gate drive board or entire drive.
Feedback Loss Go To Freq. PI Feedback Loss	Cause: PI feedback source is incorrectly installed or not working. (Effective when b5-12 is set to 3). Remedy: Confirm that the PID feedback source is installed and working properly. Drive response is controlled by b5-12 and b5-13.
Feedback Loss Wire Break PI Feedback Loss	Cause: The analog input programmed for PID feedback has gone above 21 mA or fallen below 3 mA. Remedy: Check wiring and feedback transducer.
Freq. Ref Pump Min (P1-06) Minimum Pump Frequency Reference	Cause: The frequency reference is set lower than P1-06. The frequency reference is internally set to the P1-06 value during this time. This will only be active when the drive is NOT in PI Mode and Minimum Pump Frequency is enabled (P1-06 > 0.00). Remedy: Increase the frequency reference to a value greater than P1-06.
Freq. Ref Thrust (P4-12) Thrust Frequency Reference	Cause: The fixed frequency reference is set to a value lower than the P4-12 (Thrust Frequency) setting. This will only be active when the drive is NOT in PI Mode and Thrust bearing is enabled (P4-12 > 0.00). Remedy: Increase the frequency reference to a value greater than P4-12.
Geo Params Chk Q2-05 to Q2-08 Geothermal Mode Parameters	Cause: The temperature parameter values are set incorrectly. The drive is running at the level set in Q2-03 due to an incorrect setting. Remedy: Set the temperature parameters in the following order: Q2-08 > Q2-07 > Q2-06 > Q2-05.
HCA Current Alarm	Cause: Drive current exceeded overcurrent warning level (150% of the rated current). Remedy: Load is too heavy: Reduce the load for applications with repetitive operations, or replace the drive. Accel/Decel times too short: Calculate torque required; increase acceleration and deceleration times (C1-01 through C1-04); or increase drive capacity. Special-purpose motor/Capacity mismatch: Check motor capacity; ensure motor is within allowable capacity range. Speed Search/Momentary Power Loss: The alarm will only appear briefly; no action needed if it clears.
HIAUX High PI Aux Lvl High PI Auxiliary Feedback Level	Cause: PI Aux Feedback has risen above the Q6-12 level for longer than the time set in Q6-13 and the drive is running in AUTO. Remedy: Lower the PI Aux Feedback level. Adjust parameters Q6-12 and Q6-13.
HIFLO High Flow Error	Cause: The meter has detected a high flow condition. The flow is too high or measured water flow has risen above P6-17 level for time set in P6-18. Remedy: Reduce the flow. Set the High Flow fault characteristics in P6-17 and P6-18. Drive response is controlled by P6-19. Auto-restart controlled by P6-19.
High Feedback High FB Sensed High Feedback Level Alarm	Cause: The feedback signal is too high (risen above P1-11 level). Remedy: Decrease the feedback signal. Set the High Feedback alarm characteristics in P1-11 and P-12. Drive response controlled by P1-13.
HISUC High Suction High Section Pressure	Cause: The suction pressure has risen above the level set in Q5-12. Remedy: Reduce the system pressure. Set the High Suction Pressure alarm characteristics in Q5-12. Drive response controlled by Q5-14. Auto-restart controlled by Q5-15.
LOAUX Low PI Aux Lvl Low PI Auxiliary Feedback Level	Cause: PI Aux Feedback has fallen below the Q6-09 level for longer than the time set in Q6-10. Remedy: Raise the PI Aux Feedback level. Adjust parameters Q6-09 and Q6-10.
LOP Loss of Prime	Cause: The pump has lost its prime (P1-22 is set to 1). Measured quantity dropped below P1-19 level for time set in P1-20. Remedy: If there is resistance in the pump, allow the system to pump water again. Set the Loss of Prime alarm characteristics in P1-18, P1-19, P1-20, and P1-21. Drive response controlled by P1-21.
LOSUC Low Suction Low Section Pressure	Cause: The suction pressure has fallen below the level set in Q5-09 for longer than the time set in Q5-10. Remedy: Increase the system pressure. Set the Low Suction alarm characteristics in Q5-09, Q5-10, and Q5-18. Drive response controlled by Q5-11.
Low City Pressure	Cause: Insufficient pressure is present on the inlet to the pump. (P4-24 logic applies). Remedy: Check pressure switch contact for correct operation. Check control wiring to drive terminal strip. Check to make sure that suction pressure is present by means of a separate measuring device.
Low Feedback Low FB Sensed Low Feedback Level Alarm	Cause: The feedback signal is too low (dropped below level set in P1-08). Remedy: Increase the feedback signal. Set the Low Feedback alarm characteristics in P1-08 and P1-09. Drive response controlled by P1-10.
Low Suction Pressure	Cause: Insufficient suction pressure is present. (Specific to P4-24 logic settings). Remedy: Check pressure switch contact and wiring. Check to make sure that suction pressure is present by means of a separate measuring device. Increase the system pressure. Set Low Suction alarm characteristics in Q5-09 and Q5-18.
Low Water in Tank	Cause: Insufficient pressure is present on the inlet to the pump (Shown when P4-24 = 2). Remedy: Check pressure switch contact and wiring. Raise the water level. Set the Low Water Level alarm characteristics in Q4-09. Drive response controlled by Q4-11.
Low WL/SP/PI-Aux Drive Disabled Low Water Level / Suction Pressure / Aux PI Feedback Disabled	Cause: Drive is not allowed to run in MEMOBUS multiplex. Water Level or Suction Pressure is below the Q4-06/Q5-06/Q6-06 setting. Remedy: Confirm that the Water Level, Suction Pressure, or Aux PI Feedback source is installed and working properly. Wait for the WL/SP/PIAuxFB to recover.
LT-1 Cooling Fan Maintenance Time	Cause: The cooling fan has reached 90% of its expected performance life. Remedy: Replace the cooling fan and set o4-03 to 0 to reset the Maintenance Monitor.
LT-2 Capacitor Maintenance Time	Cause: The main circuit and control circuit capacitors have reached 90% of their expected performance lives. Remedy: Replace either the control board or the entire drive. Contact Yaskawa or sales representative.
LT-3 Soft Charge Bypass Relay Maintenance Time	Cause: The DC bus soft charge relay has reached 90% of expected performance life. Remedy: Replace either the control board or the entire drive. Contact Yaskawa or sales representative.
LT-4 IGBT Maintenance Time (50%)	Cause: IGBTs have reached 50% of their expected performance life. Remedy: Check the load, carrier frequency, and output frequency.
Main FdBk Lost Using Backup FB Main Feedback Device (H3-xx = B) lost	Cause: Wire-break on Analog Input Terminal programmed for Primary PI Feedback or Transducer is broken. Remedy: Check the connection of the Main Feedback transducer. Replace Main PI Feedback Transducer.
Net Flow Meter Lost, Chk Source Net Flow Meter Loss	Cause: The flow meter function has not received a valid flow rate from another drive (when P1-01 = 3, P6-01 > 0, P9-40 = 3). Remedy: Set P9-40 to 0 if the drive has an operational flow meter connected to an analog or pulse input terminal. If another drive on the MEMOBUS network has a flow meter, confirm that drive is online with parameter settings P6-01 > 0 and P9-40 = 0.
NETSCAN Waiting for Master	Cause: Drive is waiting for a message from the master. No message received within time set in P9-28. Remedy: Increase the P9-26 setting to account for network latency. Verify that there is a drive on the network with parameter P1-01 set to 3 and P9-27 to 0. Check network connections and verify H5-01 and P9-25 settings for all drives on the network.
NMS Not Maintaining Setpoint	Cause: The setpoint cannot be maintained and P1-17 is set to 1. Feedback deviates from setpoint > P1-15 level. Remedy: Check for a blocked impeller, over cycling, or broken pipe. Set the Not Maintaining Setpoint alarm characteristics in P1-16 and P1-17. Drive response controlled by P1-17.
oH Heatsink Overheat	Cause: The temperature of the heatsink exceeded the overheat pre-alarm level set to L8-02. Surrounding temp too high, fan stopped, or airflow restricted. Remedy: Check surrounding temperature; install fan/AC if needed. Replace cooling fan if stopped (reset o4-03). Provide proper installation space; clear debris/dust from fan and cooling fins.
oH2 Drive Overheat Warning	Cause: An external device triggered an overheat warning in the drive (Input S1 through S8). Remedy: Search for the device that tripped the overheat warning. Remove the cause of the problem.
oH3 Motor Overheat	Cause: Motor overheat signal entered to multi-function analog input terminal exceeded alarm level. Remedy: Repair the PTC input wiring if faulty. Check machine status (e.g., locked up). Check load size, accel/decel times, cycle times. Reduce load or increase drive capacity. Adjust V/f pattern (E1-04 to E1-10) reducing E1-08 and E1-10. Check motor-rated current and motor cooling system.
oH5 Motor Overheat (NTC Input)	Cause: The motor temperature exceeded the level set to L1-16 (or L1-18 for motor 2). Remedy: Reduce the load. Check the ambient temperature.
oL1 Motor Overload	Cause: The electronic motor overload protection tripped. Possible causes include: Load is too heavy. Cycle times are too short during acceleration/deceleration. Motor driven below rated speed with high load. Output voltage is too high. Wrong motor rated current set in E2-01. Base frequency set incorrectly. Electrical thermal protection characteristics do not match. Motor overheated by overexcitation operation. Speed Search parameters set incorrectly. Output current fluctuation due to power supply loss. Remedy: Reduce the load or increase the speed. Increase acceleration/deceleration times (C1-01 through C1-04). Use a motor designed for low speed range if necessary. Adjust V/f pattern (reduce E1-08 and E1-10). Check motor nameplate and correct parameter E2-01. Check motor nameplate and correct Base Frequency (E1-06). Install an external thermal relay if characteristics don't match. Reduce excitation deceleration gain (n3-13) or adjust L3-04. Enable Speed Estimation Speed Search (b3-24 = 1) after Auto-Tuning. Check power supply for phase loss.
oL2 Drive Overload	Cause: The thermal sensor of the drive triggered overload protection. Load is too heavy. Acceleration or deceleration time is too short. The output voltage is too high. Drive capacity is too small. Overload occurred when operating at low speeds. Excessive torque compensation. Remedy: Reduce the load. Increase settings for acceleration and deceleration times (C1-01 to C1-04). Adjust preset V/f pattern (reduce E1-08 and E1-10). Replace the drive with a larger model (one frame size larger). Lower the carrier frequency (C6-02). Reduce torque compensation gain (C4-01).
oL3 Overtorque Detection 1	Cause: The current has exceeded the value set for torque detection (L6-02) for longer than the allowable time (L6-03). Parameter settings are not appropriate for the load. Fault on the machine side (e.g., machine is locked up). Remedy: Check L6-02 and L6-03 settings. Check the status of the load. Remove the cause of the fault.
oL4 Overtorque Detection 2	Cause: The current has exceeded the value set for Overtorque Detection 2 (L6-05) for longer than the allowable time (L6-06). Remedy: Check the settings of parameters L6-05 and L6-06.
ov DC Bus Overvoltage	Cause: The DC bus voltage exceeded the trip point. Surge voltage present in the drive input power. The motor is short-circuited. Ground current has overcharged the main circuit capacitors. Noise interference causes the drive to operate incorrectly. Remedy: Install a DC link choke or an AC reactor. Check motor power cable, relay terminals, and motor terminal box for short circuits. Review solutions for handling noise interference. Check control circuit lines and grounding. If magnetic contactor is the noise source, install a surge protector to the MC coil. Set number of fault restarts (L5-01) to a value other than 0.
PoC Pump Over Cycle	Cause: The pump has exceeded the number of cycles set in P2-10 in the time set in P2-11 and P2-12 is set to 1 (alarm). Remedy: Set the Pump Over Cycle alarm characteristics in P2-10 and P2-11. Drive response to this condition is controlled by P2-12 (Over Cycling Mode).
R-DNE-S Remote Drive Disable	Cause: Terminal S□ (H1-0□ = 95) has been closed for the time set in P4-26, Remote Drive Disable On-Delay. Remedy: Remove conditions causing the terminal to close.
rUn Motor Switch during Run	Cause: A motor switch command was entered during run. Remedy: Change the operation pattern so that the motor switch command is entered while the drive is stopped.
SE MEMOBUS/Modbus Communication Test Mode Error	Cause: A digital input set to 67H (MEMOBUS/Modbus test) was closed while the drive was running. Remedy: Stop the drive and run the test again.
SPL Suction Pressure Loss	Cause: Wire-break detection for suction pressure. An analog input programmed for setting 23 "WaterLvl/Suction" has dropped below 3 mA or risen above 21 mA for longer than 1 second. Remedy: Repair pressure sensor or wiring.
THo Thermistor Disconnect	Cause: The thermistor used to detect motor temperature has become disconnected. Remedy: Check the thermistor wiring.
TrPC IGBT Maintenance Time (90%)	Cause: IGBTs have reached 90% of their expected performance life. Remedy: Replace the drive.
UL3 Undertorque Detection 1	Cause: The current has fallen below the minimum value set for torque detection (L6-02) for longer than the allowable time (L6-03). Parameter settings are not appropriate for the load. There is a fault on the machine side. Remedy: Check the settings of parameters L6-02 and L6-03. Check the load for any problems.
UL4 Undertorque Detection 2	Cause: The current has fallen below the minimum value set for torque detection (L6-05) for longer than the allowable time (L6-06). Remedy: Check L6-05 and L6-06 settings. Check the load for any problems.
UL6 Motor Underload	Cause: The load has fallen below the underload curve defined in L6-14. The output current has fallen below the motor underload curve for longer than the time set to L6-03. Remedy: Adjust the value set to L6-14 so that output current remains above the motor underload curve during normal operation.
Uv Undervoltage	Cause: DC bus voltage dropped below the level specified in L2-05 while the drive was stopped and a Run command was entered. Phase loss in the drive input power. Loose wiring in the drive input power terminals. Problem with drive input power voltage. Drive internal circuitry is worn (Capacitors). Drive input power transformer is too small. Air inside the drive is too hot. CHARGE light is broken or disconnected. Remedy: Check for wiring errors in the main circuit drive input power. Tighten terminals as specified. Check the voltage and lower it to be within limits if necessary. Check capacitor maintenance time (U4-05). Replace control board/drive if > 90%. Check capacity of the drive input power transformer. Check temperature inside the drive. Replace control board or entire drive.
voF Output Voltage Detection Error	Cause: Problem detected with the voltage on the output side of the drive. Hardware is damaged or internal drive module MC/FAN overheat. Remedy: Lower ambient temperature. Replace the control board or the entire drive.
WLL Water Level Loss	Cause: An analog input programmed for setting 23 "WaterLvl/Suction" has dropped below 3 mA or risen above 21 mA for longer than 1 second. Remedy: Repair level sensor or wiring.
WL/SP/PIAux Lost Analog Input Lost	Cause: Network Water Level/Suction Pressure/Aux PI Feedback is being used because a wire-break was detected with the analog signal. Defective or broken analog input source. Wire-break detected with the Water Level / Suction Pressure analog signal. Remedy: Confirm that the Water Level, Suction Pressure, or Aux PI Feedback source is installed and working properly. Confirm that the Q4-16, Q5-19, or Q6-19 settings are correct. Set P9-50 to 3 if the drive does not have an analog input source.
WrUn Waiting for Run	Cause: The Run command has been applied and the b1-11 Back Spin Timer is active. Remedy: Adjust Back Spin Timer b1-11 to the desired delay time. The drive will start normally after the timer expires.
oPE01 Drive Capacity Setting Fault	Cause: The drive model selection (o2-04) and the actual capacity of the drive are not the same. Remedy: Correct the value set to o2-04.
oPE02 Parameter Range Setting Error	Cause: Parameters were set outside the possible setting range. (Use U1-18 to find parameters set outside the range). Remedy: Set parameters to the proper values. Note: When multiple errors occur simultaneously, other errors are given precedence over oPE02.
oPE03 Multi-Function Input Selection Error	Cause: A contradictory setting is assigned to multi-function contact inputs H1-01 to H1-08. The same function is assigned to two multi-function inputs (Excludes "Not used" and "External Fault"). Up command set but Down command not set (or vice versa). Run/Stop command for 2-wire sequence set, but Forward/Reverse command was not. "Drive Enable" is set to multi-function input S1 or S2. Simultaneous settings of: Up/Down, Hold Accel/Decel Stop, Analog Freq Reference Hold, Offset Frequency Calculations. Up/Down command and PID control enabled simultaneously. NC and NO input conflicts (e.g., External Search Command 1 vs 2, Fast Stop NO vs NC). H2-xx is set to 38 (Drive Enabled) and H1-xx is not set to 6A. Remedy: Ensure all multi-function inputs are assigned to different functions. Properly set the functions required for use in combination with other functions. Check if contradictory settings have simultaneously been assigned to the multi-function input terminals. Set b5-01 to 0 to disable control PID or disable the Up/Down command. Correct the settings for the multi-function input terminal parameters.
oPE04 Initialization Required, Term <-> Ctrl Chg	Cause: The drive, control board, or terminal board have been replaced and the parameter settings between the control board and the terminal board no longer match. Remedy: Set A1-03 to 5550 to load the parameter settings stored in the terminal board to the drive. Initialize parameters after drive replacement by setting A1-03 to 1110 or 2220.
oPE05 Run Command/Frequency Reference Source Selection Error	Cause: Frequency reference is assigned to an option card (b1-01 = 3) but card is not connected. The Run command is assigned to an option card (b1-02 = 3) but card is not connected. Frequency reference is assigned to pulse train input (b1-01 = 4) and terminal RP is not set for frequency reference input (H6-01 > 0). Remedy: Reconnect the input option card to the drive. Set H6-01 to 0.
oPE07 Multi-Function Analog Input Selection Error	Cause: A contradictory setting is assigned to multi-function analog inputs H3-02, H3-10, or H3-06 and PID functions conflict. At least two analog input terminals are set to the same function. Remedy: Change the settings to H3-02, H3-10, and H3-06 so that functions no longer conflict. Note: Both 0 (Frequency Reference Bias) and F (Not Used) can be set simultaneously.
(No Code Displayed) PID Feedback/Pulse Train Conflict	Cause: The following simultaneous contradictory settings: H3-xx = B (PID Feedback) while H6-01 (Pulse Train Input) = 1 (PID Feedback). H3-xx = C (PID Target Value) while H6-01 = 2 (pulse train input sets PID target). Remedy: Disable one of the PID selections.
oPE09 PID Control Selection Fault	Cause: PID control function selection is incorrect (Requires b5-01 = 1 to 4). b5-15 is not set to 0.0 (PID Sleep Function Operation Level). The stopping method is set to either DC Injection Braking or coast to stop with a timer. b5-01 is set to 1 or 2 (PID enabled), but lower limit (d2-02) is not 0 while reverse output is enabled. b5-01 is set to 3 or 4 (PID enabled), but lower limit (d2-01) is not 0. Remedy: Set b5-15 to a value other than 0.0. Set the stopping method to coast to stop or ramp to stop (b1-03 = 0 or 1). Correct the parameter settings for d2-01 or d2-02.
oPE10 V/f Data Setting Error	Cause: V/f pattern setting error. One of the following setting errors has occurred: E1-09 ≤ E1-07 < E1-06 ≤ E1-11 ≤ E1-04. Remedy: Correct the settings for E1-04, E1-06, E1-07, E1-09, and E1-11.
oPE11 Carrier Frequency Setting Error	Cause: The following simultaneous contradictory settings have occurred: C6-05 > 6 and C6-04 > C6-03 (carrier frequency lower limit is greater than the upper limit). The upper and lower limits between C6-02 and C6-05 are contradictory. Remedy: Correct the setting for the carrier frequency parameters.
oPE18 Online Tuning Parameter Setting Error	Cause: One of the following errors occurred while online tuning was enabled in OLV (A1-02 = 2): E2-02 was set below 30% of the original default value. E2-06 was set below 50% of the original default value. E2-03 = 0. Remedy: Set E2-02, E2-03, and E2-06 to the correct values.
oPE28 Sequence Timer Error	Cause: One or more of the sequence timers is not set in the correct order. Contradictory settings: S2-01 > S2-02 S2-06 > S2-07 S2-11 > S2-12 S2-16 > S2-17 Remedy: Correct the parameter settings.
oPE29 Geothermal Set Error	Cause: P1-01 parameter selection is not compatible with Geothermal Mode (b1-01 = 5). Remedy: Confirm b1-01 and P1-01 parameter settings.
oPE30 Flow Meter Input Error	Cause: Analog and pulse flow meters are programmed simultaneously (H6-01=5 and H3-xx=22). Flow meter scaling is set to 0 and the flow meter is being used as PID feedback. Remedy: Reprogram H6-01, H3-02, H3-06, or H3-10. Reprogram P6-01, P1-02, or b5-01.
oPE31 Water Level/Suction Pressure/PI Aux	Cause: One or both of the following conditions are present: More than one of these parameters is set to a non-zero value: Q4-01, Q5-01, or Q6-01. Both Water Level/Suction Pressure (H3-xx = 23) and PI Aux FB Level (H3-xx = 27) are programmed. Remedy: Confirm parameter settings of Q4-01, Q5-01, Q6-01, H3-02, H3-06, and H3-10.
oPE32 Incompatible Network Water Level/Suction Pressure Mode	Cause: Low Water Level or Suction Pressure Turn-Off Method (P9-51) is restricted to Water Level Source of Analog Only (P9-50 = 0). Remedy: Confirm parameter settings for P9-50 and P9-51.
oPE33 Parameter selection is incompatible with the selected network P9-99	Cause: When P1-01 = 3 (MEMOBUS Networking) and P9-99 = 0, one of the following parameters has been set: P9-01 = 2 (Stop History) P9-05 = 3 (Follow Lead Speed) Q4-01 > 0 (Water Level Enabled) Q5-01 > 0 (Suction Pressure Control Enabled) P6-01 > 0 (Flow Meter Enabled) and P9-40 = 3 (Network) Remedy: Confirm parameter settings for P1-01, P9-99, P6-01, P9-05, P9-40, Q4-01, and Q5-01.
oPE34 De-Scale Setting Error	Cause: The De-scale function is not allowed while Anti-Jam or MEMOBUS Multiplex is enabled. Remedy: Review settings of parameters P1-01, P7-01, or P8-01.
End1 Excessive V/f Setting	Cause: The torque reference exceeded 20% during Auto-Tuning OR The results from Auto-Tuning the no-load current exceeded 80%. Remedy: Prior to Auto-Tuning, verify the information on the motor nameplate. Enter proper values from motor nameplate to parameters T1-02 and T1-04 and repeat Auto-Tuning. If possible, disconnect the motor from the load and perform Auto-Tuning. If the load cannot be uncoupled, use the current Auto-Tuning results.
End2 Motor Iron-Core Saturation Coefficient	Cause: Motor data entered during Auto-Tuning was incorrect OR Results from Auto-Tuning are outside the parameter setting range. Remedy: Make sure the data entered to the T1 parameters match the information written on the motor nameplate. Restart Auto-Tuning and enter the correct information. Check and correct faulty motor wiring. Disconnect the motor from machine and perform Rotational Auto-Tuning.
End3 Rated Current Setting Alarm	Cause: The correct current rating printed on the motor nameplate was not entered into T1-04. Remedy: Check the setting of parameter T1-04. Check the motor data and repeat Auto-Tuning.
End4 Adjusted Slip Calculation Error	Cause: The calculated slip is outside the allowable range. Remedy: Make sure the data entered for Auto-Tuning is correct. If possible, perform Rotational Auto-Tuning. If not possible, perform Stationary Auto-Tuning 2.
End5 Resistance Tuning Error	Cause: The calculated resistance value is outside the allowable range. Remedy: Double-check the data entered for the Auto-Tuning process. Check the motor and motor cable connection for faults.
End6 Leakage Inductance Alarm	Cause: The calculated leakage inductance value is outside the allowable range. Remedy: Double-check the data entered for the Auto-Tuning process.
End7 No-Load Current Alarm	Cause: The entered no-load current value was outside the allowable range OR Auto-Tuning results were less than 5% of the motor rated current. Remedy: Check and correct faulty motor wiring. Double-check the data entered for the Auto-Tuning process.
Er-01 Motor Data Error	Cause: Motor data entered during Auto-Tuning was incorrect, Motor output power and settings do not match, or Motor rated current and detected no-load current are inconsistent. Remedy: Check that the motor data entered to T1 parameters matches motor nameplate input before Auto-Tuning. Check the drive and motor capacities. Correct settings of T1-02 and T1-04. Check the motor rated current and no-load current. Correct settings of T1-04 and E2-03.
Er-02 Minor Fault	Cause: An alarm was triggered during Auto-Tuning. Remedy: Exit the Auto-Tuning menu, check the alarm code, remove the alarm cause, and repeat Auto-Tuning.
Er-03 STOP Button Input	Cause: Auto-Tuning canceled by pressing STOP button. Remedy: Auto-Tuning did not complete properly. Restart Auto-Tuning.
Er-04 Line-to-Line Resistance Error	Cause: Motor data entered incorrect, Results outside parameter range, or Faulty motor cable connection. Remedy: Make sure the data entered to the T1 parameters match the information written on the motor nameplate. Check and correct faulty motor wiring. Restart Auto-Tuning and enter the correct information.
Er-05 No-Load Current Error	Cause: Motor data entered incorrect, Results outside parameter range, or The load was too high during Rotational Auto-tuning. Remedy: Make sure the data entered to T1 parameters matches motor nameplate. Check and correct faulty motor wiring. Disconnect the motor from machine and restart Auto-Tuning. If motor and load cannot be uncoupled make sure the load is lower than 30%. If a mechanical brake is installed, make sure it is fully lifted during tuning.
Er-08 Rated Slip Error	Cause: Motor data entered incorrect, Results outside parameter range, or The load was too high during rotational Auto-tuning. Remedy: Make sure the data entered to the T1 parameters match the information written on the motor nameplate. Check and correct faulty motor wiring. Disconnect the motor from machine and restart Auto-Tuning (ensure load is < 30%). If a mechanical brake is installed, make sure it is fully lifted during tuning.
Er-09 Acceleration Error	Cause: Motor did not accelerate for the specified time, Torque limit too low, or Load too high. Remedy: Increase the acceleration time (C1-01). Disconnect the machine from the motor if possible. Check L7-01 and L7-02 settings and increase if needed. Ensure mechanical brake is fully lifted.
Er-11 Motor Speed Fault	Cause: Torque reference is too high. Remedy: Increase the acceleration time (C1-01). Disconnect the machine from the motor if possible.
Er-12 Current Detection Error	Cause: One of the motor phases is missing, Current exceeded rating, Current too low, or Attempted Auto-Tuning without motor connected. Remedy: Check motor wiring and correct any problems. Check for shorts between motor lines. Close any magnetic contactors used between motors. Connect the motor and restart Auto-Tuning. If Current detection signal error: Replace control board or entire drive.
Er-13 Leakage Inductance Error	Cause: Drive was unable to complete tuning for leakage inductance within 300 seconds. Remedy: Check all wiring and correct any mistakes. Check the motor rated current value written on the motor nameplate and enter the correct value to T1-04.
Er-17 Reverse Prohibited Error	Cause: Drive is prohibited from rotating the motor in reverse while attempting to perform Inertia Tuning. Remedy: Inertia Auto-Tuning cannot be performed if the drive is restricted from rotating in reverse. Assuming it is acceptable for the application to rotate in reverse, set b1-04 to 0 and then perform Inertia Tuning.
CoPy Writing Parameter Settings (flashing)	Cause: Parameters are being written to the drive. Remedy: This is not an error.
CPyE Error Writing Data	Cause: Failed writing parameters. Remedy: Attempt to write parameters again.
CSEr Copy Unit Error	Cause: Hardware fault. Remedy: Replace the HOA keypad or the USB Copy Unit.
dFPS Drive Model Mismatch	Cause: The drives used in the copy and write process are not the same model. Remedy: Verify the model number of the drive from which the parameters were copied and the model of the drive to which those parameters will be written. Make sure the two drives are the same model and have the same software version.
End Task Complete	Cause: Finished reading, writing, or verifying parameters. Remedy: This is not an error.
iFEr Communication Error	Cause: A communication error occurred between the drive and the HOA keypad/USB unit OR Non-compatible cable used. Remedy: Check the cable connection. Use the cable originally packaged with the USB Copy Unit.
ndAT Model, Voltage Class, Capacity Mismatch	Cause: Drives have different electrical specifications/capacities OR Device used to write is blank. Remedy: Make sure model numbers and specifications are the same for both drives. Make sure all connections are correct, and copy the parameter settings onto the USB Copy Unit or the HOA keypad.
rdEr Error Reading Data	Cause: Failed while attempting to read parameter settings from the drive. Remedy: Press and hold the READ key on the USB Copy Unit for at least one second to have the unit read parameters from the drive.
rEAd Reading Parameter Settings (flashing)	Cause: Displayed while the parameter settings are being read onto the USB Copy Unit. Remedy: This is not an error.
vAEr Voltage Class, Capacity Mismatch	Cause: The drive from which the parameters were copied and the drive on which the Verify mode is being performed have different specifications. Remedy: Make sure electrical specifications and capacities are the same for both drives.
vFyE Parameter settings mismatch	Cause: Indicates that parameter settings that have been Read and loaded onto the Copy Unit or HOA keypad are different. Remedy: To synchronize parameters, either write the parameters saved on the USB Copy Unit or HOA keypad onto the drive, or Read the parameter settings on the drive onto the USB Copy Unit.
vrFy Comparing Parameter Settings (flashing)	Cause: The Verify mode has confirmed that parameters settings on the drive and parameters read to the copy device are identical. Remedy: This is not an error.

 

How to Read iQPump1000 Faults via Keypad & PC

In 2026, troubleshooting an industrial pump station requires looking at the system history, not just the current error. The iQPump1000 offers several ways to do this:

• Real-Time Clock (RTC) Logs: Unlike smaller drives, the iQPump1000 stamps faults with the actual Date and Time (provided the battery is active). Navigate to Monitor > Fault History to see exactly when the pump tripped (e.g., “LPo at 2026-06-15 14:30”).
• U2 Fault Trace: Access the “Black Box” data directly on the keypad:
  • U2-01: Current Fault.
  • U2-02: Previous Fault.
  • U2-13/14 (Terminal Status): Crucial for seeing if a “Low Level Float Switch” or “Flow Switch” was open at the moment of the trip.
• DriveWizard Industrial: Connect via USB to view the Pump Curve Monitor. This allows you to graph Pressure (PSI) vs. Frequency (Hz) to determine if the pump is mechanically worn or if the PID settings are unstable.

Frequently Asked Questions (FAQ)

Q: What is the difference between an Alarm and a Fault on the iQPump1000?

A:

• Alarm (Flashing ‘ALM’ LED): The drive detects a warning (like “High Pressure” or “Sleep Mode”) but continues to regulate the system.
• Fault (Solid ‘ALM’ LED): The drive trips to protect the pump or motor. The output stops, and the system pressure will drop.

Q: How do I reset a Yaskawa iQPump1000 fault?

A: Once the water supply is verified:

• Press the RESET key on the keypad.
• If using the “Hand-Off-Auto” keypad, switching to OFF and back to AUTO often resets the fault.
• Cycle the main power disconnect.

Q: What does “oPr” mean?

A: “oPr” stands for Minimum Pressure (Open Transducer). This usually means the 4-20mA pressure transducer signal has been lost (wire broken) or the system pressure has dropped below the safety threshold set in parameter P1-15, indicating a pipe break.