Alternator Problem
Note: This symptom is not an electronic system fault.
Probable Causes
- Alternator drive belt and tensioner
- Alternator
- Charging circuit
Recommended Actions
Note: The procedures have been listed in order of probability. Complete the procedures in order.
Show/hide table
| Troubleshooting Test Steps | Values | Results |
|---|---|---|
1. Alternator Drive Belt and Tensioner A. Inspect the condition of the alternator drive belt. B. Check the belt tension. Check the automatic belt tensioner. Note: Excessive belt tension can result in damage to the alternator. |
Drive belt |
Result: The alternator drive belts are not in good condition or the belt tension is incorrect. If the alternator drive belts are worn or damaged, replace the belts. Refer to Disassembly and Assembly for the correct procedure. If necessary, replace the automatic belt tensioner. Refer to Disassembly and Assembly for the correct procedure. Result: The alternator drive belts are in good condition and the belt tension is correct. Proceed to Test Step 2. |
2. Alternator A. Verify that the alternator is operating correctly. Refer to Special Instruction, REHS0354, "Charging System Troubleshooting" for the proper testing procedures. |
Alternator |
Result: The alternator is not operating correctly. Repair the alternator or replace the alternator, as necessary. Refer to Disassembly and Assembly, "Alternator - Remove" and Disassembly and Assembly, "Alternator - Install" for the correct procedure. Result: The alternator is operating properly. Proceed to Test Step 3. |
3. Charging Circuit A. Inspect the battery cables, wiring, and connections in the charging circuit. |
Charging circuit |
Result: The charging circuit is not operating correctly. Clean all connections and tighten all connections. Replace any faulty parts. Result: The charging circuit is operating correctly. Contact the Technical Communicator at a Cat dealer. |
Caterpillar Information System:
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