Alternator FR Signal Circuit Troubleshooting

Alternator FR Signal Circuit Troubleshooting

1. Start the engine, and let it idle.

2. Monitor the ALTERNATOR in the DATA LIST with the HDS.

3. Check if the indicated percentage varies when the headlight switch is turned on.

Does the percentage vary?

YES -

The alternator signal circuit is OK.�

NO -

Go to step 4.

4. Turn the headlight switch off, and turn the ignition switch to LOCK (0).

5. Jump the SCS line with the HDS.

6. Disconnect the alternator 4P connector.

7. Disconnect PCM connector C (49P).

8. Check for continuity between PCM connector terminal C44 and body ground.





Is there continuity?

YES -

Repair short in the wire between the PCM(C44) and the alternator.�

NO -

Update the PCM if it does not have the latest software PCM Update, or substitute a known-good PCM, then recheck. If the symptom/indication goes away with a known-good PCM, replace the original PCM Service and Repair.�