Kohler CH740 Engine Engine

• Battery short circuits
  Fix: Disconnect the battery before generator set installation or maintenance. Remove all jewelry before servicing the equipment. Use tools with insulated handles. Remove the negative (--) lead first when disconnecting the battery. Reconnect the negative (--) lead last when reconnecting the battery. Never connect the negative (--) battery cable to the positive (+) connection terminal of the starter solenoid. Do not test the battery condition by shorting the terminals together.
• High Total Harmonic Distortion (THD) Measured THD is above 25% GenTHDHigh
  Cause: Generator power output is not stable and having high THD (THD means total harmonic distortion, which is a metric to measure the power quality. If the THD is high, the performance of your electronics will be affected; for example, you may see flickering lights).
• Generator was overloaded. GeneratorVoltageImbalance OR GeneratorComBusPhaseDifferenceOOR
  Cause: Generator breaker in IQ System Controller tripped, and the generator is disconnected.
  Fix: The system will try to reconnect the generator in 5 minutes. You should: • Open IQ System Controller door, turn off the generator breaker and turn it on again. (When you open IQ System Controller, the generator breaker lever will not be in ON position) • Ensure you do not overload the system while the generator is running.
• Generator voltage and/or frequency out of spec while in generator mode and generator is connected EnpowerGeneratorVoltHighTrip OR EnpowerGeneratorVoltLowTrip OR EnpowerGeneratorFreqHighTrip OR EnpowerGeneratorFreqLowTrip
  Cause: The generator gets disconnected
• Generator not stopping GeneratorStopFailed
  Cause: Generator continues to run even though user preferences indicate it should have stopped.
  Fix: Check if the generator 2-wire start/stop wiring to IQ System Controller is loose. Turn off the generator manually and contact installer or Enphase customer support.
• Generator not starting GeneratorStartFailed
  Cause: The generator does not start as selected in user preferences.
  Fix: Check if the generator 2-wire start/stop wiring to IQ System Controller is loose. Check whether the generator breaker at the unit was tripped (if so turn the breaker off and then on. Also switch the controller to the auto position), whether the generator is out of fuel, or the starting battery of the generator was dead. Contact your installer or Enphase customer support if the problem persists.
• The generator shuts down due to a main power overload condition. Main Power Overload Shutdown
• Issues arise when paralleling the generator with other systems or units. Faults Related to Paralleling
• Communication Lost with Secondary Controller LossOfComm2
• This generator does not know if the metering is connected or the orientation of the connection. This means that the generators can’t share load accurately until this information is known. MeterUnknown
  Cause: System commissioning and startup not yet complete. See the APM instructions.
• The two generators that are intended to be paralleled have incompatible model numbers. CfgModelNum
  Cause: Incorrect configuration of one of the generators. Different generator types. The paralleled generator sets must be the same kW model. (i.e. two 14 kW or two 20 kWor 26 kW models).
• The system voltage of the two generators intended to be paralleled is not the same. CfgSysVolt
  Cause: One of the two generators is incorrectly configured. Intermittent connections on RBUS network wiring.
• The primary controller has lost communication with the secondary controller. (A secondary controller was detected, then communication was lost.) LossOfComm2
  Cause: RBUS disconnected, secondary controller battery disconnected, updating firmware in secondary controller, or intermittent RBUS connections.
• The power metering on this controller gives a signal that is not consistent with the system configuration. Reversing the power direction does not resolve the problem. ErraticSig
  Cause: Bad wiring to the CT. Too much tension on wires from the CT to the controller.
• The generator has been attempting to synchronize for over 2 minutes without success. SyncFailure
  Cause: Generator is hunting. Advanced speed control settings need adjustment. Load is changing frequently to disturb the online generator.

Compiled from service & troubleshooting documentation across every generator set that uses the Kohler CH740.

Pooled from every document that names this exact engine — confirm the interval and part number against your unit's serial number.

Parts cataloged across all variants of this engine family — verify the exact part fits your specific variant and serial number before ordering.

Parts listed by aftermarket suppliers as fitting this engine — leads compiled from supplier catalogs; verify the exact part for your serial number.