How to troubleshoot excessive load on the alternator of the Caterpillar 320C excavator and low or irregular alternator charging rate Possible causes and troubleshooting methods are as follows.

 CAT Caterpillar ET 4 Diagnostic Adapter Truck Diagnostic Tool-high quality

A (1) The drive belt of the alternator is loose. Adjust drive belt for correct tension.correct tension.

  (2) Charging, grounding circuit or battery connector failure. Check all cables and connectors. All 

joints 

must be clean and tightened. Replace any failed parts. 

(3) Alternator regulator failure. Repair or replace alternator regulator. 

 (4) Alternator brush failure. Install new brushes.  

(5) Rectifier diode failure. Replace the failed rectifier diode. (6) Rotor (excitation coil) failure. Install 

new rotor. 2023 CAT ET 2023A 2022A & 2019C Full Service Download and Installation Service

B (1) The alternator or its regulator connector is loose. Tighten all connections to the alternator or its 

regulator.

  (2) Alternator regulator failure. Install a new alternator regulator.