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Charging System Indicator Circuit Troubleshooting

NOTE: Check for stored DTCs in the PGM-FI before troubleshooting the charging system indicator.
  1. Turn the ignition switch to ON (II).

    Does the charging system indicator come on? 

    YES  -Go to step 2.

    NO  -Go to step  14.

  2. Start the engine. Hold the engine speed at 2, 000 rpm for 1 minute.

    Does the charging system indicator go off? 

    YES  -Charging system indicator circuit is OK. Go to the alternator and regulator circuit troubleshooting (see ALTERNATOR AND REGULATOR CIRCUIT TROUBLESHOOTING  ).

    NO  --Go to step 3.

  3. Do the gauge control module self-diagnostic function procedure (see SELF-DIAGNOSTIC FUNCTION ).

    Does the charging system indicator flash? 

    YES  -Go to step 4.

    NO  -Replace the gauge control module (see GAUGE CONTROL MODULE REPLACEMENT ).

  4. Turn the ignition switch to LOCK (0).
  5. Disconnect the alternator 4P connector.
  6. Turn the ignition switch to ON (II).

    Does the charging system indicator go off? 

    YES  -Replace the alternator (see ALTERNATOR REMOVAL AND INSTALLATION  ), or repair the alternator (see ALTERNATOR OVERHAUL  ).

    NO  -Go to step 7.

  7. Turn the ignition switch to LOCK (0).
  8. Connect the HDS to the DLC (see step 2 under GENERAL TROUBLESHOOTING INFORMATION ).
  9. Turn the ignition switch to ON (II).
  10. Make sure the HDS communicates with the vehicle and the PCM. If it does not communicate, troubleshoot the DLC circuit (see DLC CIRCUIT TROUBLESHOOTING ).
  11. Jump the SCS line with the HDS, then turn the ignition switch to LOCK (0).
    NOTE: This step must be done to protect the PCM from damage.
  12. Disconnect PCM connector C (49P).
  13. Check for continuity between PCM connector terminal C42 and body ground.
    Fig 1: Checking Continuity Between PCM Connector Terminal C42 And Body Ground
    G08051973Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  -Repair a short in the wire between the alternator 4P connector terminal No. 3 and PCM connector terminal C42.

    NO  -Update the PCM if it does not have the latest software (see KNOCK SENSOR REPLACEMENT ), or substitute a known-good PCM (see SUBSTITUTING THE PCM ), then recheck. If the symptom/indication goes away with a known-good PCM, replace the original PCM (see PCM REPLACEMENT ).

  14. Do the gauge control module self-diagnostic function procedure (see SELF-DIAGNOSTIC FUNCTION ).

    Does the charging system indicator flash? 

    YES  -Go to step 15.

    NO  -Replace the gauge control module (see GAUGE CONTROL MODULE REPLACEMENT ).

  15. Turn the ignition switch to LOCK(0).
  16. Disconnect the alternator 4P connector.
  17. Connect alternator 4P connector terminal No. 3 and body ground with a jumper wire.
    Fig 2: Connecting Alternator 4P Connector Terminal No. 3 And Body Ground With Jumper Wire
    G08051974Courtesy of AMERICAN HONDA MOTOR CO., INC.
  18. Turn the ignition switch to ON (II).

    Does the charging system indicator come on? 

    YES  -Replace the alternator (see ALTERNATOR REMOVAL AND INSTALLATION  ), or repair the alternator (see ALTERNATOR OVERHAUL  ).

    NO  -Disconnect the jumper wire, then go to step  20.

  19. Turn the ignition switch to LOCK (0).
  20. Connect the HDS to the DLC (see step 2 under GENERAL TROUBLESHOOTING INFORMATION ).
  21. Turn the ignition switch to ON (II).
  22. Make sure the HDS communicates with the vehicle and the PCM. If it does not communicate, troubleshoot the DLC circuit (see DLC CIRCUIT TROUBLESHOOTING ).
  23. Jump the SCS line with the HDS, then turn the ignition switch to LOCK (0).
    NOTE: This step must be done to protect the PCM from damage.
  24. Disconnect PCM connector C (49P).
  25. Check for continuity between PCM connector terminal C42 and alternator 4P connector terminal No. 3.
    Fig 3: Checking Continuity Between PCM Connector Terminal C42 And Alternator 4P Connector Terminal No. 3
    G08051975Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  -Update the PCM if it does not have the latest software (see KNOCK SENSOR REPLACEMENT ), or substitute a known-good PCM (see SUBSTITUTING THE PCM ), then recheck. If the symptom/indication goes away with a known-good PCM, replace the original PCM (see PCM REPLACEMENT ).

    NO  -Repair an open in the wire between the alternator 4P connector terminal No. 3 and PCM connector terminal C42.

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