M11 Industrial Operation and Maintenance – Alternator Not Charging or Insufficient Charging

Symptom Tree  

Alternator belt is loose

Check the alternator belt tension. Refer to Procedure 013-021 (Belt Tensioner, Automatic – Alternator) in Section A.


Battery cables or connections are loose, broken, or corroded (excessive resistance)

Check the battery cables and connections.


Batteries have malfunctioned

Check the condition of the batteries. Replace the batteries, if necessary. Refer to the OEM service manual.


Electrical system is “open” (blown fuses, broken wires, or loose connections)

Check the fuses, wires, and connections. Refer to the OEM service manual and the manufacturer’s wiring diagrams.


Alternator pulley is loose on the shaft

Tighten the pulley. Refer to Procedure 013-005 (Drive Belt, Alternator) in Section A.

Contact a Cummins Authorized Repair Facility

Last Modified:  09-Dec-2004