Alternator FR Signal Circuit Troubleshooting
- Start the engine, and let it idle.
- Monitor the ALTERNATOR in the DATA LIST with the HDS.
- 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.
- Turn the headlight switch off, and turn the ignition switch to LOCK (0), or press the engine start/stop button to select the OFF mode.
- Jump the SCS line with the HDS.
- Disconnect the alternator 4P connector.
- Disconnect ECM/PCM connector C (49P).
- Check for continuity between ECM/PCM connector terminal C44 and body ground.
Courtesy of AMERICAN HONDA MOTOR CO., INC.
Is there continuity?
YES - Repair short in the wire between the ECM/PCM (C44) and the alternator.
NO - Update the ECM/PCM if it does not have the latest software (see ECM/PCM UPDATE ), or substitute a known-good ECM/PCM (see SUBSTITUTING THE ECM/PCM ), then recheck. If the symptom/indication goes away and the ECM/PCM was updated, troubleshooting is complete. If the symptom/indication goes away and the ECM/PCM was substituted, replace the original ECM/PCM (see ECM/PCM REPLACEMENT ).