General

UNDERVOLTAGE

UnclassifiedElectrical

What This Code Means

Engine stops; 'UNDERVOLTAGE' Fault Lamp Illuminates

Possible Causes

  • •Under-voltage
  • •Equipment overload
  • •Faulty wiring
  • •Faulty AVR (Automatic Voltage Regulator)

Suggested Actions

  1. 1Disconnect the alternator from the load by turning off the circuit breaker (handle down).
  2. 2Reset the fault by turning the Control Switch to 'STOP' and restart engine.
  3. 3Check voltage on panel meters.
  4. 4If voltage is normal, check the load characteristics to ensure the system is not overloaded.
  5. 5If voltage remains low and cannot be adjusted to the normal level using the voltage adjust potentiometer (if fitted), check the voltage at the alternator terminals with an independent meter.
  6. 6If voltage at the terminals is correct, check wiring.
  7. 7Check AVR.
  8. 8Refer to the Alternator Manual.

Related General Fault Codes

OVERVOLTAGELOW BATTERY VOLTAGELBVBATTERY CHARGER FAILUREUNDERSPEEDOVERSPEEDNOT IN AUTO MODELOW OIL PRESSURELOW FUEL LEVELLOW COOLANT TEMPLOW COOLANT LEVEL
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