Drives (VFDs)
Yaskawa GA500 AC Drive fault codes
What all 141 Yaskawa GA500 AC Drive fault codes mean, in plain words, with a risk grade for each. These come from the manufacturer's own manual. The fix for each one is in WERCS Diagnose.
Get the fixes · plans from $49/moUpdated November 4, 2026
| Code | What it means | Risk |
|---|---|---|
| CE | Modbus Communication Error A communication error on the Modbus network has occurred, which stops the drive from receiving control commands. | YELLOW |
| CF | Control Fault Incorrect motor parameters or settings have caused a control fault, forcing the drive to stop the motor. | YELLOW |
| E5 | MECHATROLINK Watchdog Timer Err The drive detected a watchdog circuit exception while receiving data, causing it to stop the motor. | YELLOW |
| EF | FWD/REV Run Command Input Error Forward and reverse commands were input simultaneously for over half a second, causing the drive to stop operating. | GREEN |
| GF | Ground Fault A ground fault occurred in the motor or wiring, causing the drive to shut down immediately. | RED |
| LF | Output Phase Loss A phase loss occurred on the drive output side, which stops power from reaching the motor. | YELLOW |
| PF | Input Phase Loss A phase loss or voltage imbalance in the input power has caused the drive to stop. | YELLOW |
| SC | Short Circuit/IGBT Failure A short circuit or ground fault occurred on the output side, immediately stopping the drive operation. | RED |
| SE | Modbus Test Mode Error A communications self-diagnostic test was attempted while the drive was running, which stops the drive from functioning normally. | GREEN |
| bb | Baseblock An external baseblock command was received by the system, which immediately stopped the drive output to the motor. | GREEN |
| oC | Overcurrent The drive output current exceeded the safe detection level, causing the drive to stop the motor. | YELLOW |
| oH | Heatsink Overheat The drive heatsink temperature exceeded the overheat alarm level, which will eventually stop the motor operation. | YELLOW |
| oS | Overspeed The motor speed exceeded the safe detection level, causing the drive to shut down the equipment. | YELLOW |
| ov | Overvoltage The internal bus voltage exceeded the safe detection level, causing the drive to stop the motor. | YELLOW |
| rF | Braking Resistor Fault The braking resistance is too low or connected incorrectly, causing the drive to halt the motor. | YELLOW |
| rH | Braking Resistor Overheat The braking resistor is overheating from excessive energy, which causes the drive to stop the motor. | YELLOW |
| rr | Dynamic Braking Transistor Fault A malfunction in the internal braking transistor has occurred, causing the drive to stop the motor. | YELLOW |
| AEr | Station Address Setting Error The communication node address is outside the permitted range, which stops the drive from communicating with the system. | GREEN |
| CP1 | Comparator 1 Limit Error The monitored value fell within the programmed limit range, triggering an error that halts the drive operation. | YELLOW |
| CP2 | Comparator 2 Limit Error The monitored value fell outside the programmed limit range, triggering an error that stops the drive. | YELLOW |
| CoF | Current Offset Fault A hardware problem or induced motor voltage has caused a current offset fault, stopping the drive from running. | YELLOW |
| CyC | MECHATROLINK CommCycleSettingErr The communications cycle setting of the controller is not in the permitted range, which causes the drive to fault and stop operating. | GREEN |
| EF0 | Option Card External Fault The communication option received an external fault or programming error, which stops the drive from running. | YELLOW |
| EF1 | External Fault (Terminal S1) An external device triggered a fault on terminal S1, causing the drive to stop the motor. | YELLOW |
| EF2 | External Fault (Terminal S2) An external device triggered a fault on terminal S2, causing the drive to stop the motor. | YELLOW |
| EF3 | External Fault (Terminal S3) An external device triggered a fault on terminal S3, causing the drive to stop the motor. | YELLOW |
| EF4 | External Fault (Terminal S4) An external device triggered a fault on terminal S4, causing the drive to stop the motor. | YELLOW |
| EF5 | External Fault (Terminal S5) An external device triggered a fault on terminal S5, causing the drive to stop the motor. | YELLOW |
| EF6 | External Fault (Terminal S6) An external device triggered a fault on terminal S6, causing the drive to stop the motor. | YELLOW |
| EF7 | External Fault (Terminal S7) An external device triggered a fault on terminal S7, causing the drive to stop the motor. | YELLOW |
| Err | EEPROM Write Error Hardware issues or electrical interference corrupted the memory data, preventing the drive from saving its settings. | YELLOW |
| FbH | Excessive PID Feedback The feedback value exceeded the high detection level, causing the drive to halt the current process. | YELLOW |
| FbL | PID Feedback Loss The feedback value dropped below the loss detection level, causing the drive to stop the motor. | YELLOW |
| HCA | High Current Alarm The drive output current exceeded the high current alarm level, which triggers an alarm but operation may continue. | GREEN |
| LF2 | Output Current Imbalance An imbalance in the output current to the motor has caused the drive to stop operating. | YELLOW |
| LoG | Log Com Error An error occurred with the keypad data logging function, which stops data recording but the drive keeps running. | GREEN |
| PGo | Encoder (PG) Feedback Loss The drive lost the feedback signal from the encoder, causing it to stop running the motor. | YELLOW |
| SCF | Safety Circuit Fault The safety circuit is broken, which immediately stops the drive and prevents the motor from running. | RED |
| TiM | Keypad Time Not Set The keypad date and time are not set, which prevents the drive from logging accurate fault times. | YELLOW |
| UL3 | Undertorque Detection 1 The drive detected an undertorque condition based on its settings, causing it to stop the motor. | YELLOW |
| UL4 | Undertorque Detection 2 The drive detected a secondary undertorque condition based on its settings, forcing the motor to stop. | YELLOW |
| UL5 | Mechanical Weakening Detection 2 The drive detected an undertorque condition related to mechanical weakening, which causes the drive to stop operating. | YELLOW |
| Uv1 | DC Bus Undervoltage The DC bus voltage dropped below the detection level, causing the drive to shut down the equipment. | YELLOW |
| Uv2 | Control Power Undervoltage The control power supply voltage dropped too low, which forces the drive to stop running the motor. | YELLOW |
| Uv3 | Soft Charge Answerback Fault There is damage to the soft charge bypass relay or contactor, which stops the drive from operating. | YELLOW |
| bAT | Keypad Battery Low Voltage The keypad battery voltage is low, which will eventually cause the keypad to lose its stored settings. | YELLOW |
| bCE | Bluetooth Communication Fault Radio interference or distance has disrupted the Bluetooth connection, preventing the mobile device from communicating with the drive. | YELLOW |
| bUS | Option Communication Error The drive lost its signal from the controller due to wiring or interference, causing the motor to stop. | YELLOW |
| boL | BrakingTransistor Overload Fault The braking transistor is broken or overloaded, which causes the drive to stop operating the motor. | YELLOW |
| dnE | Drive Disabled A terminal set for drive enable turned off, which immediately stops the drive from running. | GREEN |
| dv7 | Polarity Judge Timeout The drive timed out while attempting to determine the motor polarity, preventing normal operation. | YELLOW |
| nSE | Node Setup Error A node setup conflict occurred during operation, which prevents the drive from running the motor normally. | YELLOW |
| oC2 | Overcurrent2 The output current exceeded its programmed limit, which forces the drive to shut down the motor. | YELLOW |
| oH1 | Heatsink Overheat The drive heatsink temperature exceeded its maximum detection level, causing the drive to shut down completely. | YELLOW |
| oH2 | External Overheat (H1-XX=B) An external device sent an overheat alarm to the drive, which triggers a warning while the booth keeps running. | GREEN |
| oH3 | Motor Overheat (PTC Input) The motor temperature exceeded the overheat alarm level, triggering a warning before the drive shuts down. | YELLOW |
| oH4 | Motor Overheat Fault (PTC Input) The motor temperature exceeded the overheat fault level, causing the drive to shut down the motor. | YELLOW |
| oL1 | Motor Overload The electronic thermal protector detected a motor overload, causing the drive to stop powering the motor. | YELLOW |
| oL2 | Drive Overload The electronic thermal protector detected a drive overload, causing the unit to stop running the motor. | YELLOW |
| oL3 | Overtorque Detection 1 The drive detected an overtorque condition based on its settings, causing it to stop the motor. | YELLOW |
| oL4 | Overtorque Detection 2 The drive detected a secondary overtorque condition based on its settings, forcing the motor to stop. | YELLOW |
| oL5 | Mechanical Weakening Detection 1 The drive detected overtorque related to mechanical weakening, causing it to halt the motor for safety. | YELLOW |
| oL7 | High Slip Braking Overload An overload occurred during high slip braking, which causes the drive to stop operating the motor. | YELLOW |
| oPr | Keypad Connection Fault The keypad is not securely connected, which prevents the drive from receiving manual inputs or commands. | YELLOW |
| rUn | Motor Switch during Run The drive received a secondary motor selection command while running, which causes the drive to stop the motor. | GREEN |
| CALL | Serial Comm Transmission Error A communication error occurred on the serial network, which prevents the drive from receiving commands to run. | GREEN |
| CPEr | Control Mode Mismatch The keypad and drive settings do not agree during backup, which prevents the parameters from being saved. | YELLOW |
| CPyE | Error Writing Data The parameter restore process did not end correctly, meaning the drive cannot operate with the new settings. | YELLOW |
| CSEr | Control Mode Mismatch The keypad is broken, which prevents the operator from changing settings or running the drive manually. | YELLOW |
| CrST | Cannot Reset The drive received a fault clearing command while a run command was active, preventing the drive from starting. | GREEN |
| CyPo | Cycle Power to Accept Changes New communication option settings on the drive have not taken effect yet, so the drive will not run. | GREEN |
| End1 | Excessive Rated Voltage Setting Auto-tuning finished with calculation errors due to excessive torque or current, meaning the drive cannot operate optimally. | YELLOW |
| End2 | Iron Core Saturation Coefficient Auto-tuning finished with calculation errors for the iron core saturation coefficient, which prevents optimal drive performance. | YELLOW |
| End3 | Rated Current Setting Alarm Auto-tuning finished with calculation errors due to an incorrect rated current value, limiting the drive performance. | YELLOW |
| End4 | Adjusted Slip Calculation Error The auto tuning process completed with calculation errors for the adjusted slip, which prevents the drive from running optimally. | YELLOW |
| End5 | Resistance Tuning Error Auto-tuning finished with calculation errors for the line-to-line resistance, meaning the drive cannot operate the motor perfectly. | YELLOW |
| End6 | Leakage Inductance Alarm Auto-tuning finished with calculation errors for leakage inductance, which prevents the drive from achieving optimal motor control. | YELLOW |
| End7 | No-Load Current Alarm Auto-tuning finished with calculation errors for the no-load current, meaning the drive will not run the motor optimally. | YELLOW |
| End8 | HFI Alarm Auto-tuning finished with calculation errors during high frequency injection tuning, which limits the drive performance during operation. | YELLOW |
| End9 | Initial Pole Detection Alarm The drive cannot calculate the correct initial pole value during tuning, which prevents optimal motor operation. | YELLOW |
| L24v | Loss of External Power 24 Supply The voltage of the backup power supply has decreased, which can prevent the drive from maintaining control power. | GREEN |
| LT-1 | Cooling Fan Maintenance Time The cooling fan has reached ninety percent of its expected performance life, but the drive continues to operate. | GREEN |
| LT-2 | Capacitor Maintenance Time The main and control circuit capacitors reached ninety percent of their expected life, though the drive still operates. | GREEN |
| LT-3 | SoftChargeBypassRelay MainteTime The soft charge bypass relay has reached ninety percent of its expected performance life while the drive continues running. | GREEN |
| LT-4 | IGBT Maintenance Time (50%) The insulated gate bipolar transistor is at half of its expected performance life, and the drive continues operating normally. | GREEN |
| PASS | Modbus Communication Test The communications test is complete, meaning the drive is now ready to resume normal booth operations. | GREEN |
| PWEr | DWEZ Password Mismatch The password entered for the backup operation is incorrect, which prevents the drive from saving the parameters. | YELLOW |
| SToF | Safe Torque OFF Hardware A hardware fault occurred in the safe disable circuit, which immediately stops the drive and shuts down the motor. | RED |
| TrPC | IGBT Maintenance Time (90%) The insulated gate bipolar transistor reached ninety percent of its expected performance life, but the drive still operates. | GREEN |
| dCE1 | Communication Error1 A temporary drive hardware problem occurred due to electrical noise, causing the drive to stop the motor. | YELLOW |
| dCE2 | Communication Error2 Electrical noise has caused a temporary drive hardware problem, forcing the drive to halt the motor. | YELLOW |
| dFPS | Drive Model Mismatch A parameter restore was attempted on a different drive model, which stops the drive from accepting settings. | YELLOW |
| dWF1 | EEPROM Memory DWEZ Data Error An error in the memory circuit or data has occurred, which stops the drive from operating correctly. | YELLOW |
| dWF2 | DriveWorksEZ Fault 2 A fault occurred in the internal drive program, which causes the drive to stop the motor. | YELLOW |
| dWF3 | DriveWorksEZ Fault 3 An internal program fault has occurred, causing the drive to halt its current operation immediately. | YELLOW |
| dWFL | DriveWorksEZ Fault A fault in the custom drive program has occurred, which stops the drive from running the motor. | YELLOW |
| iFEr | Keypad Communication Error A communications error occurred between the keypad and the drive, preventing manual control of the booth equipment. | YELLOW |
| ndAT | Error Received Data The parameter settings differ between the keypad and drive or are missing, which stops the backup process. | YELLOW |
| rdEr | Error Reading Data A data backup was attempted while the copy function was disabled, preventing the drive from saving parameters. | YELLOW |
| vAEr | Voltage Class, Capacity Mismatch The power supply or capacity settings differ between the keypad and drive, which halts the backup process. | YELLOW |
| vFyE | Parameters do not Match The parameters backed up in the keypad do not match the drive, which prevents successful data verification. | YELLOW |
| CPF06 | Control Circuit Error (EEPROM memory Data Error) A memory data error occurred during a write operation, which prevents the drive from functioning properly. | YELLOW |
| EP24v | External Power 24V Supply The main circuit voltage decreased so the backup power supply is running the drive, limiting normal booth operation. | GREEN |
| Er-01 | Motor Data Error Auto-tuning failed because the entered motor data is incorrect, preventing the drive from running the booth motor. | YELLOW |
| Er-02 | Drive in an Alarm State Auto-tuning failed due to an active alarm or wiring issue, which stops the drive from operating the equipment. | YELLOW |
| Er-03 | STOP Button was Pressed The auto tuning process did not complete because the stop button was pressed, which halts the drive setup. | YELLOW |
| Er-04 | Line-to-Line Resistance Error Auto-tuning failed to measure the line-to-line resistance correctly, preventing the drive from operating the motor properly. | YELLOW |
| Er-05 | No-Load Current Error Auto-tuning failed to measure the no-load current correctly, which stops the drive from running the equipment optimally. | YELLOW |
| Er-08 | Rated Slip Error Auto-tuning failed to measure the rated slip correctly, meaning the drive cannot control the motor perfectly. | YELLOW |
| Er-09 | Acceleration Error The motor did not accelerate properly during auto-tuning, which prevents the drive from completing its setup process. | YELLOW |
| Er-10 | Motor Direction Error The motor rotated in the wrong direction during auto-tuning, causing the drive to halt the setup process. | YELLOW |
| Er-11 | Motor Speed Error The torque reference during acceleration was too high during auto-tuning, which stops the drive from finishing setup. | YELLOW |
| Er-12 | Current Detection Error The drive detected a current error during auto-tuning, preventing the system from completing the motor setup process. | YELLOW |
| Er-13 | Leakage Inductance Alarm The drive could not complete tuning for leakage inductance in time, which halts the motor setup process. | YELLOW |
| Er-14 | Motor Speed Error 2 The motor speed was too high during inertia tuning, causing the drive to stop the setup procedure. | YELLOW |
| Er-15 | Torque Saturation Error The output torque exceeded the limit during inertia tuning, which forces the drive to abort the setup. | YELLOW |
| Er-16 | Inertia ID Error The inertia found by the drive was out of range during tuning, which stops the setup process. | YELLOW |
| Er-17 | Reverse Prohibited Error Inertia tuning failed because reverse operation is disabled, preventing the drive from completing the motor setup process. | YELLOW |
| Er-18 | Back EMF Error The induced voltage tuning result was outside the applicable range, which halts the drive setup procedure immediately. | YELLOW |
| Er-19 | PM Inductance Error The permanent magnet motor inductance tuning results were out of range, preventing the drive from finishing setup. | YELLOW |
| Er-20 | Stator Resistance Error The permanent magnet motor stator resistance tuning results were out of range, which stops the setup process. | YELLOW |
| Er-25 | HighFreq Inject Param Tuning Err The motor data is incorrect for high frequency injection tuning, preventing the drive from completing the setup. | YELLOW |
| oFA00 | Option Not Compatible with Port The connected option card is not compatible with the port, preventing the drive from functioning properly. | YELLOW |
| oFA01 | Option Fault/ Connection Error The option card was changed during operation, causing the drive to fault and stop the motor. | YELLOW |
| oPE01 | Drive Capacity Setting Error The programmed capacity setting does not match the drive model, which prevents the drive from starting the booth. | YELLOW |
| oPE02 | Parameter Range Setting Error The programmed parameter settings are outside the applicable range, which stops the drive from running the equipment. | YELLOW |
| oPE03 | Multi-Function Input Setting Err The settings for multi-function inputs overlap or conflict, preventing the drive from starting the booth motor. | YELLOW |
| oPE05 | Run Cmd/Freq Ref Source Sel Err The run command or frequency reference assignment is incorrect, which prevents the drive from operating the booth. | YELLOW |
| oPE07 | Analog Input Selection Error The programmed settings for analog inputs overlap or conflict, which stops the drive from starting the equipment. | YELLOW |
| oPE08 | Parameter Selection Error An incompatible function was programmed for the selected control method, preventing the drive from running the booth. | YELLOW |
| oPE09 | PID Control Selection Fault The proportional integral derivative control parameters conflict with other settings, which stops the drive from operating normally. | YELLOW |
| oPE10 | V/f Data Setting Error The voltage and frequency pattern parameters do not meet required conditions, preventing the drive from starting the motor. | YELLOW |
| oPE11 | Carrier Frequency Setting Error The carrier frequency settings are incorrect or out of range, which stops the drive from running the booth. | YELLOW |
| oPE13 | Pulse Monitor Selection Error The pulse monitor selection is set incorrectly relative to frequency scaling, preventing the drive from operating the equipment. | YELLOW |
| oPE16 | Energy Saving Constants Error The energy saving parameters are outside the applicable setting range, which stops the drive from starting the motor. | YELLOW |
| PE1, PE2 | PLC Faults The communication option detected a fault, which stops the drive from receiving commands from the controller. | YELLOW |
| oFA10, oFA11 | Option Card Error Occurred at Option Port (CN5) An error has occurred within the option card, causing the drive to stop running the equipment. | YELLOW |
| oFA03 - oFA06 | Option Card Error Occurred at Option Port (CN5) A fault has occurred in the option card, which causes the drive to stop operating the booth. | YELLOW |
| oFA12 to oFA17 | Option Card Connection Error (CN5) A connection fault has occurred in the option card, which forces the drive to shut down the booth. | YELLOW |
| oFA30 to oFA43 | Communication Option Card Connection Error (CN5) A communication fault has occurred in the option card, causing the drive to stop the equipment. | YELLOW |
| CPF02, CPF03, CPF08, CPF11 - CPF14, CPF16 - CPF24, CPF38 | Control Circuit Error A hardware problem occurred in the drive control circuit, which completely shuts down the booth motor operation. | YELLOW |
Every code comes from the manufacturer's own manual. Subscribers see which manual and page.