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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. Remove the engine compartment covers (see ENGINE COMPARTMENT COVER REPLACEMENT ).
  2. Turn the ignition switch to ON (II), or press the engine start/stop button to select the ON mode.

    Does the charging system indicator come on? 

    YES  - Go to step 3.

    NO  - Go to step  15.

  3. 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 . ■

    NO  - Go to step 4.

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

    Does the charging system indicator flash? 

    YES  - Go to step 5.

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

  5. Turn the ignition switch to LOCK (0), or press the engine start/stop button to select the OFF mode.
  6. Disconnect the alternator 4P connector.
  7. Turn the ignition switch to ON (II), or press the engine start/stop button to select the ON mode.

    Does the charging system indicator go off? 

    YES  - Replace the alternator  or repair the alternator . ■

    NO  - Go to step 8.

  8. Turn the ignition switch to LOCK (0), or press the engine start/stop button to select the OFF mode.
  9. Connect the HDS to the DLC (see HOW TO USE THE HDS (HONDA DIAGNOSTIC SYSTEM) ).
  10. Turn the ignition switch to ON (II), or press the engine start/stop button to select the ON mode.
  11. Make sure the HDS communicates with the vehicle and the ECM/PCM. If it does not communicate, troubleshoot the DLC circuit (see DLC CIRCUIT TROUBLESHOOTING ).
  12. Jump the SCS line with the HDS, then turn the ignition switch to LOCK (0), or press the engine start/stop button to select the OFF mode.
    NOTE: This step must be done to protect the ECM/PCM from damage.
  13. Disconnect ECM/PCM connector C (49P).
  14. Check for continuity between ECM/PCM connector terminal C42 and body ground.
    Fig 1: Checking Continuity Between ECM/PCM Connector Terminal C42 And Body Ground
    G08068586Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

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

    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 with a known-good ECM/PCM, replace the original ECM/PCM (see ECM/PCM REPLACEMENT ). ■

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

    Does the charging system indicator flash? 

    YES  - Go to step 16.

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

  16. Turn the ignition switch to LOCK (0), or press the engine start/stop button to select the OFF mode.
  17. Disconnect the alternator 4P connector.
  18. 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
    G08068587Courtesy of AMERICAN HONDA MOTOR CO., INC.
  19. Turn the ignition switch to ON (II), or press the engine start/stop button to select the ON mode.

    Does the charging system indicator come on? 

    YES  - Replace the alternator  or repair the alternator . ■

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

  20. Turn the ignition switch to LOCK (0), or press the engine start/stop button to select the OFF mode.
  21. Connect the HDS to the DLC (see HOW TO USE THE HDS (HONDA DIAGNOSTIC SYSTEM) ).
  22. Turn the ignition switch to ON (II), or press the engine start/stop button to select the ON mode.
  23. Make sure the HDS communicates with the vehicle and the ECM/PCM. If it does not communicate, troubleshoot the DLC circuit (see DLC CIRCUIT TROUBLESHOOTING ).
  24. Jump the SCS line with the HDS, then turn the ignition switch to LOCK (0), or press the engine start/stop button to select the OFF mode.
    NOTE: This step must be done to protect the ECM/PCM from damage.
  25. Disconnect ECM/PCM connector C (49P).
  26. Check for continuity between ECM/PCM connector terminal C42 and alternator 4P connector terminal No. 3.
    Fig 3: Checking Continuity Between ECM/PCM Connector Terminal C42 And Alternator 4P Connector Terminal No. 3
    G08068588Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  - 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 with a known-good ECM/PCM, replace the original ECM/PCM (see ECM/PCM REPLACEMENT ). ■

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

  27. Install the engine compartment covers (see ENGINE COMPARTMENT COVER REPLACEMENT ).
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