Cummins

2678

UnclassifiedGeneral

What This Code Means

Battery charging alternator is not functioning correctly or is sensing too high of external battery voltage

Possible Causes

  • •Faulty Engine DC Alternator
  • •Faulty Engine DC Alternator Or Open Circuit
  • •Open Circuit

Suggested Actions

  1. 1Check the wiring of the alternator for open circuits.
  2. 2If the appropriate output is not observed, replace the DC alternator.
  3. 3Measure the output voltage of the alternator to the battery while the engine is running (normal charging voltage is 12-14 VDC in a 12 V system or 24-26 VDC in a 24 V system).
  4. 4Measure the output voltage of the alternator to the battery while the engine is running.
  5. 5Replace the DC alternator if appropriate output is not observed.

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