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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 (see 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 (see ALTERNATOR REMOVAL AND INSTALLATION ) or repair the alternator (see ALTERNATOR OVERHAUL )

    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 Honda Diagnostic System (HDS) to the data link connector (DLC) (see step 2 on GENERAL TROUBLESHOOTING INFORMATION )
  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 powertrain control module (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 PCM from damage
  13. Disconnect PCM connector C (49P)
  14. Check for continuity between PCM connector terminal C42 and body ground
    Fig 1: Checking Continuity Between PCM Connector Terminal C42 And Body Ground
    G05986543Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

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

    NO  -Update the PCM if it does not have the latest software (see ECM/PCM UPDATE ), or substitute a known-good PCM (see SUBSTITUTING THE ECM/PCM ), then recheck If the symptom/indication goes away with a known-good PCM, replace the original 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
    G05986544Courtesy 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 (see ALTERNATOR REMOVAL AND INSTALLATION ) or repair the alternator (see ALTERNATOR OVERHAUL )

    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 step 2 on GENERAL TROUBLESHOOTING INFORMATION )
  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 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 PCM from damage
  25. Disconnect PCM connector C (49P)
  26. 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
    G05986545Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

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

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

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