Kohler RDT troubleshooting: 13 fault codes and 57 symptom-cause-remedy entries from the manufacturer's own service documentation.
Kohler RDT — full specs, parts & maintenance.
| Code | Meaning | Cause | Remedy |
|---|---|---|---|
| Failure to Transfer | Failure to Transfer — GEN or Utility Source Position LED flashes 2 times/second. | Source not available. | Check source voltage, frequency, stability. |
| Failure to Transfer | Failure to Transfer — GEN or Utility Source Position LED flashes 2 times/second. | Controller does not recognize an available source. | Check switches, circuit breakers for open circuit. Check source connections to the ATS. Check source voltage and compare to source pickup and dropout levels. See Sections 5.3 and 5.4. |
| Failure to Transfer | Failure to Transfer — GEN or Utility Source Position LED flashes 2 times/second. | Transfer switch mechanism problem. | See Section 4.5, Transfer Switch Troubleshooting. |
| Auxiliary Switch Fault | Auxiliary Switch Fault — GEN Position and Utility Source Position LEDs flash alternately 2 times/second. | Controller cannot determine the transfer switch position. | Check wiring and connections to position microswitches. See the schematic drawing for connections. Test position microswitch operation. Replace microswitch if necessary. See Section 7. Transfer switch in intermediate position. Disconnect power and manually operate the transfer switch. See instructions in the ATS operation/installation manual. Inspect for signs of coil damage or overheating and replace coil if necessary. |
| Failure to Acquire Standby | Failure to Acquire Standby — GEN Available LED flashes 2 times/second. | Open circuit breaker. | Check and close ATS source and generator set circuit breakers. |
| Failure to Acquire Standby | Failure to Acquire Standby — GEN Available LED flashes 2 times/second. | Generator set master switch not in AUTO. | Move generator set master switch to the AUTO position. |
| Failure to Acquire Standby | Failure to Acquire Standby — GEN Available LED flashes 2 times/second. | Loose engine start connection. | Check connections. |
| Failure to Acquire Standby | Failure to Acquire Standby — GEN Available LED flashes 2 times/second. | No engine start command from ATS. | See Section 5.9. |
| Failure to Acquire Standby | Failure to Acquire Standby — GEN Available LED flashes 2 times/second. | Other generator set problem. | Troubleshoot the generator set. See generator set service manual. |
| Failure to Acquire Standby | Failure to Acquire Standby — GEN Available LED flashes 2 times/second. | ATS does not recognize the standby source. | Check for loose source connections. Check for open switch or circuit breaker. Check source voltage and frequency and compare to pickup and dropout levels. See Section 5.4. |
| Failure to Acquire Emergency Source | Failure to Acquire Emergency Source Warning — the transfer switch does not sense voltage from the generator set within 75 seconds after signaling the generator set to start. | Engine start circuit or generator set operation problem; generator set shuts down when the engine start contacts are closed (for example, shutting the generator set down by moving the master switch to OFF during the engine cooldown time delay). | Check the engine start circuit and the generator set operation. Determine the reason for the generator set shutdown and then reset the fault as described in Section 4.4.1. The fault clears when the system acquires the emergency source. |
| Failure to Transfer | Failure to Transfer Warning — a signal to transfer is sent to the contactor and the position-indicating contacts do not indicate a complete transfer. | Position-indicating contacts do not indicate a complete transfer. | The controller will attempt to transfer three times before indicating the fault. If the transfer switch is in the Normal position, the Engine Cooldown time delay is executed and then the engine start contacts open to stop the generator set. See Section 4.4.1 to reset the fault condition. |
| Auxiliary Switch Fault | Auxiliary Switch Fault — the position-indicating contacts indicate that the ATS position changed when no transfer was called for, or both auxiliary switches are open or closed so that the controller is unable to determine the transfer switch position. | Position-indicating contacts indicate that the ATS position changed when no transfer was called for; both auxiliary switches are open or closed so that the controller is unable to determine the transfer switch position. | If the transfer switch is in the Normal position, the Engine Cooldown time delay is executed and then the engine start contacts open to stop the generator set. See Section 4.4.1 to reset the fault condition. |
| Symptom | Cause | Remedy |
|---|---|---|
| ATS fails to operate and no LEDs are lit | No power to the transfer switch/controller. | Close circuit breakers leading from power sources to the transfer switch. Troubleshoot power to the system. See Section 5.1. |
| Generator set does not start when the normal source fails (Also see Figure 4-2) | Generator set master switch is in the OFF position or the batteries are not charged or connected. | Place the generator set master switch in the AUTO position. Check that the generator set batteries are charged and connected. |
| Generator set does not start when the normal source fails (Also see Figure 4-2) | Engine start circuit is malfunctioning. | Troubleshoot. See Section 5.9. |
| Generator set does not start when the normal source fails (Also see Figure 4-2) | Generator set is malfunctioning. | See the generator set operation or service manual. |
| Generator set does not start with the exerciser (Also see Figure 4-2 and Figure 4-4) | Generator set master switch is in the OFF position or the batteries are not charged or connected. | Place the generator set master switch in the AUTO position. Check that the generator set batteries are charged and connected. |
| Generator set does not start with the exerciser (Also see Figure 4-2 and Figure 4-4) | Engine start circuit is malfunctioning. | See Section 5.9 to troubleshoot the engine start circuit. |
| Generator set does not start with the exerciser (Also see Figure 4-2 and Figure 4-4) | Generator set is malfunctioning. | See the generator set operation or service manual. |
| Generator set does not shut down (Also see Figure 4-6) | Generator set master switch is in the RUN position. | Place the generator set master switch in the AUTO position. |
| Generator set does not shut down (Also see Figure 4-6) | The engine start circuit is malfunctioning, or the exerciser is operating. | If the exerciser has recently been in the Set position or is in the Enable position, wait for the exerciser period of 20 minutes to end. If the generator set continues to run, see Section 5.9 to troubleshoot the engine start circuit. |
| Generator set does not shut down (Also see Figure 4-6) | Time delay engine cooldown (TDEC) has not timed out. (after retransferring the load to the normal source) | Check operation. Enough time must pass for the engine cooldown time delay to expire. |
| Generator set does not shut down (Also see Figure 4-6) | Generator set is malfunctioning. | See the generator set operation or service manual. |
| ATS fails to transfer the load to the emergency source after the generator set starts (Also see Figure 4-5) | Generator set circuit breaker is open. | Close circuit breakers leading from the generator set to the ATS. |
| ATS fails to transfer the load to the emergency source after the generator set starts (Also see Figure 4-5) | Time delay normal-to-emergency (TDNE) has not timed out. | Check operation. Enough time must pass for the time delay normal-to-emergency to time out. |
| ATS fails to transfer the load to the emergency source after the generator set starts (Also see Figure 4-5) | Generator voltage is out of range or emergency source sensing circuits are malfunctioning. | Check the emergency source voltage. Repair or adjust generator set if the output voltage is it is out of range, otherwise see Section 5.4. |
| ATS fails to transfer the load to the emergency source after the generator set starts (Also see Figure 4-5) | Transfer switch operation problems. | See Section 4.5, Transfer Switch Troubleshooting. |
| ATS fails to retransfer the load to the normal source after the normal source returns (Also see Figure 4-5) | Normal source circuit breaker is open. | Close circuit breakers leading from the normal source to the transfer switch. |
| ATS fails to retransfer the load to the normal source after the normal source returns (Also see Figure 4-5) | Emergency-to-normal retransfer time delay has not timed out. | Check time delay settings. See Figure 2-2. Enough time must elapse for the time delay emergency-to-normal timer to time out. |
| ATS fails to retransfer the load to the normal source after the normal source returns (Also see Figure 4-5) | Normal source voltage levels are out of range. | Check the normal source voltage. See Section 5.1. |
| ATS fails to retransfer the load to the normal source after the normal source returns (Also see Figure 4-5) | Normal source sensing circuits are malfunctioning. | See Section 5.3, Normal Source Sensing. |
| ATS fails to retransfer the load to the normal source after the normal source returns (Also see Figure 4-5) | Transfer switch operation problems. | See Section 4.5, Transfer Switch Troubleshooting. |
| Transfer switch mechanism is binding | Debris is in the transfer switch mechanism. | Clean the transfer switch assembly. See Section 3.2.2. |
| Transfer switch mechanism is binding | Transfer switch mechanism is damaged. | Replace the transfer switch assembly. See Section 7.5. |
| ATS operates erratically or operates out of specifications | Power supply problems/loose connections, incorrect transfer switch controller operation/calibration. | For erratic operation, check wiring for loose connections especially those that supply power to the controller or in the affected circuit. Check the power supply. See Section 5.1. See Section 5.5 for problems related to time delays in the operating sequence. For problems related to dropout and pickup specifications see Section 5.3 for the normal source or Section 5.4 for the emergency source. |
| Source available LED off when Source is available | Controller does not recognize an available source. | Check switches, circuit breakers for open circuit. Check source connections to the ATS. Check source voltage and compare to source pickup and dropout levels. See Sections 2.5.1 and 5.1. |
| Source available LED off when Source is available | Malfunctioning LED. | Replace the controller’s switch/LED membrane if one or more LEDs do not light. If no LEDs light, troubleshoot power and connections to the controller. |
| Position LED not lit | Position microswitch malfunction. | Check the operation of the position microswitches. See Section 5.10. |
| Position LED not lit | Transfer switch in intermediate position. | Manually operate the transfer switch and check the position LED operation. See Section 2.6. Check for evidence of solenoid coil damage. Replace the solenoid assembly if necessary. See the Table of Contents to locate solenoid assembly replacement procedures for your model transfer switch. |
| Position LED not lit | LEDs not functioning. | Replace the controller’s switch/LED membrane if one or more LEDs do not light. If no LEDs light, troubleshoot power and connections to the controller. |
| Exerciser does not operate when expected (Also see Figure 4-4) | Controller reset has cleared the exercise timer. | Set the exerciser on the desired time and day. |
| Engine does not start. | Generator set master switch not in the AUTO position. | Move the generator set master switch to the AUTO position. |
| Engine does not start. | Engine start circuit wiring between the transfer switch and the generator set faulty. | Check the engine start circuit wiring between the transfer switch and the generator set. |
| Engine does not start. | Controller’s engine start contacts do not operate correctly. | Replace the control board. See Section 7.4. |
| Engine does not start. | Accessory board problem. | Troubleshoot the accessory board. See Section 5.12. |
| Engine does not start. | Engine starting battery connections or generator set problem. | Check the engine starting battery connections and troubleshoot the generator set. See the generator set manuals. |
| Exerciser does not start or stop the generator set engine. | Exercise switch operation faulty. | Check the Exercise switch operation. See Section 5.8, Switch/LED Membrane. Does the Exercise switch open and close correctly? |
| Exerciser does not start or stop the generator set engine. | Optional accessory board installed. | Check DIP switch 1, 1 week/2 week exercise. Remove the accessory board and check ATS operation without it. |
| Exerciser does not start or stop the generator set engine. | Engine start contacts not open. | Replace the controller circuit board. |
| Exerciser does not start or stop the generator set engine. | Engine start circuit wiring short circuit or generator set problem. | Check the engine start circuit wiring for short circuits. Troubleshoot the generator set. |
| Exerciser does not start or stop the generator set engine. | Utility source not available. | Exerciser will not transfer the load or stop the engine if the utility source is not available. Check source circuit breakers and see Sections 5.1 and 5.3. |
| Exerciser does not start or stop the generator set engine. | Programmable exerciser installed. | Check settings. See TT-1403. Disconnect the programmable exerciser and check ATS operation without it. |
| ATS does not transfer the load. | Test or exercise not set for loaded run. | Hold test or exercise button at least 6 seconds. |
| ATS does not transfer the load. | Transfer switch mechanism binding. | Clean and/or service the ATS mechanism. See Section 4.5. |
| ATS does not transfer the load. | Source voltage or frequency not within acceptable range. | Check the source voltage and compare to pickup and dropout settings. See Section 5.1 and Figure 2-5. For transfer to emergency source, also check the source frequency. Normal source: wait for the utility source to return and stabilize. Emergency source: Adjust/service the generator set. See the generator set instruction manuals. |
| ATS does not transfer the load. | Source circuit breakers/switches open. | Close the source circuit breakers/switches. |
| ATS does not transfer the load. | Transfer time delay not expired. | Wait for time delays to expire. |
| ATS does not transfer the load. | Source-sensing wiring or operation faulty. | Check source-sensing wiring and operation. See Section 5.3 or 5.4. |
| ATS does not transfer the load. | Position indication LED does not agree with actual transfer switch position. | Check the position-indicating microswitch wiring and operation. See Section 5.10. |
| ATS does not transfer the load. | Solenoid coil voltage or coil-operation control switches faulty. | Check voltage to the solenoid coil(s). Also check coil-operation control switches on 400 amp switches. See Section 5.11. |
| Generator set continues to run after transfer to Normal source, end test, or exercise period expires. | Engine cooldown time delay not expired. | Wait for engine cooldown time delay to expire. Check for additional engine cooldown time delay on generator set controller. See generator set operation manual. |
| Generator set continues to run after transfer to Normal source, end test, or exercise period expires. | Optional Accessory Board installed with incorrect time delay settings. | Check engine cooldown time delay setting, Accessory Board time delay switch 1. See the ATS operation/installation manual. Verify that switch is not in between settings. Remove the Accessory board and retest ATS operation. |
| Generator set continues to run after transfer to Normal source, end test, or exercise period expires. | Generator set master switch not in the AUTO position. | Move the generator set master switch to the AUTO position. |
| Generator set continues to run after transfer to Normal source, end test, or exercise period expires. | Utility source not available. | ATS will not transfer if it does not see an acceptable source. Check utility source voltage and source sensing. See Sections 5.1 and 5.3. |
| Generator set continues to run after transfer to Normal source, end test, or exercise period expires. | Engine start contacts not open. | Test engine start contacts. See Section 5.9. Are the engine start contacts open? |
| Generator set continues to run after transfer to Normal source, end test, or exercise period expires. | Generator set problem. | Troubleshoot the generator set. See the generator set manuals. |
| Generator set continues to run after transfer to Normal source, end test, or exercise period expires. | Test button operation faulty. | Check Test button operation. See Switch/LED membrane, Section 5.8. Replace the Switch/LED membrane. |
| Generator set continues to run after transfer to Normal source, end test, or exercise period expires. | Engine start circuit wiring short circuit. | Check the engine start circuit wiring for a short circuit. Repair or replace faulty wiring. |
| Generator set continues to run after transfer to Normal source, end test, or exercise period expires. | Controller circuit board faulty. | Replace the controller circuit board. |
Fault codes and symptom→remedy steps extracted from this model’s service/owner documentation; verify against the official manual before servicing.
Documented causes: Engine cooldown time delay not expired.; Optional Accessory Board installed with incorrect time delay settings.; Generator set master switch not in the AUTO position.; Utility source not available.. See the table for the matching fixes.
Documented causes: Test or exercise not set for loaded run.; Transfer switch mechanism binding.; Source voltage or frequency not within acceptable range.; Source circuit breakers/switches open.. See the table for the matching fixes.
Documented causes: Exercise switch operation faulty.; Optional accessory board installed.; Engine start contacts not open.; Engine start circuit wiring short circuit or generator set problem.. See the table for the matching fixes.