Cummins/Onan KTA38-G2 Engine Engine

Shared across brands: Cummins/Onan, Onan

• Engine fails to start, or starts, runs and then stops
  Fix: Refer to Troubleshooting Section in the Operator’s manual
• The FAULT 1 or FAULT 2 fault lamp lights. Engine shuts down immediately, or engine runs for several seconds and then shuts down, or engine continues to run. FAULT 1 or FAULT 2
  Fix: The nature of the fault is an optional selection that is determined when the set installation is designed. The undesignated fault functions may also be programmed for non-shutdown or non-time delay.
• SWITCH OFF lamp flashes.
  Fix: Indicates Run/Stop/Remote switch is in the STOP position which will prevent automatic starting if an automatic transfer switch is used. Move the Run/Stop/ Remote switch to the Remote position for automatic starting.
• PRE LO OIL PRES lamp lights. Engine continues to operate.
  Fix: Check oil level, lines and filters. If oil system is okay but oil level is low, replenish. Reset control and restart. Contact your Dealer or Distributor if oil pressure is not in the range of 35 to 55 psi (21 to 379 kPa).
• PRE Hi ENGINE TEMP lamp lights. Engine continues to operate.
  Fix: A. Reduce load if possible by turning off non-critical loads. b. Check air inlets and outlets and remove any obstructions to airflow. c. Open doors or windows in generator area to increase ventilation.
• OVERCRANK lamp lights and engine stops cranking.
  Fix: A. Check for empty fuel tank, fuel leaks, or plugged fuel lines and correct as required. b. Check for dirty fuel filter and replace if necessary (see Maintenance section). c. Check for dirty or plugged air filter and replace if necessary (see Maintenance section). d. Refer to Step 5. e. Reset the control and restart after correcting the problem. Contact your Dealer or Distributor for service if none of the above.
• No-AC output voltage.
  Fix: Field breaker is tripped. Reset breaker.
• LO OIL PRES lamp lights. Engine shuts down.
  Fix: Check oil level, lines and filters. If oil system is okay but oil level is low, replenish. Reset control and restart. Contact your Dealer or Distributor if oil pressure is not in the range of 35 to 55 psi (21 to 379 kPa).
• LO FUEL Lamp lights. Engine shuts down and LO OIL PRES lamp lights.
  Fix: Indicates engine has run out of fuel. Check fuel level and replenish as required.
• LO FUEL lamp lights. Engine continues to run.
  Fix: Indicates diesel fuel supply is running low. Check fuel supply and replenish as required.
• LO ENG TEMP lamp lights. Set is in standby mode but is not operating.
  Fix: Lamp lights when engine coolant temperature is 70°F (21°C) or lower. Since the lamp goes out after the engine warms up, there should be no cause for alarm even during initial generator set operation.
• HI ENG TEMP lamp lights. Engine shuts down.
  Fix: Allow engine to cool down completely before proceeding with the f
• Fault lamp lights but no fault exists.
  Fix: The monitor board or a sensor may be at fault. Contact your Dealer or Distributor for service.
• Engine will not crank.
  Fix: Indicates possible fault with control or starting system. Check for the following conditions: a. Fault lamp on. Correct fault and reset control. b. Poor battery cable connections. Clean the battery cable terminals and tighten connections. c. Replace the battery if necessary. d. Contact your Dealer or Distributor for assistance if none of the above.
• Engine starts from generator control panel but will not start automatically or from a remote panel.
  Fix: Note: The Run/Stop/Remote switch must be in the Remote position for automatic or remote starting. Engine wil not crank. Indicates possible fault with control or starting system. Check for the following conditions: a. Fault lamp on. Correct fault and reset control. b. Poor battery cable connections. Clean the battery cable terminals and tighten connections. c. Replace the battery if necessary. d. Contact your Dealer or Distributor for assistance if none of the above.

Compiled from service & troubleshooting documentation across every generator set that uses the Cummins/Onan KTA38-G2.

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