Cummins/Onan 4BT3.9Gl Engine Engine

• Over Current 1471
• Low Coolant Level 197
• Weak Battery 1442
• Under Frequency 1448
• Too Long in Idle 2342
• The FAULT 1 or FAULT 2 fault lamp lights. Engine shuts down immediately, engine runs for several seconds and then shuts down, or engine continues to run.
  Fix: The standard undesignated fault functions are programmed to shut down the set when a fault is sensed. Fault 1 is time delayed while Fault 2 is immediate. 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.
• Speed/Hz Match 1469
• Speed Signal Lost 121
• Shutdown After Battle Short 1123
• Short Circuit 1445
• Same features as Fault 1 (Normally set for timed shutdown). FAULT 2
• Remote Emergency Stop 1434
• Pre-Low Oil Pressure Sensor 143
• Pre-High Cool Temp 146

Compiled from service & troubleshooting documentation across every generator set that uses the Cummins/Onan 4BT3.9Gl.

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