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MIL Circuit Troubleshooting

  1. Turn the ignition switch ON (II).
  2. Do the gauge self-diagnostic function (see SELF-DIAGNOSTIC FUNCTION ).

    Does the MIL indicator flash? 

    YES  -Go to step 3.

    NO  -Substitute a known-good gauge control module, and recheck. If the MIL circuit is OK, replace the original gauge control module (see GAUGE CONTROL MODULE REPLACEMENT ).

  3. Connect the HDS to the DLC (see GENERAL TROUBLESHOOTING INFORMATION ).
  4. Check the SCS in the DATA LIST with the HDS.

    Is a short indicated? 

    YES  -Go to step 5.

    NO  -Update the ECM/PCM if it does not have the latest software (see UPDATING THE ECM/PCM ), 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  ).

  5. Turn the ignition switch OFF.
  6. Disconnect ECM/PCM connector E (31P), then disconnect the HDS.
  7. Check for continuity between ECM/PCM connector terminal E16 and body ground.
    Fig 1: Checking Continuity Between ECM/PCM Connector Terminal E16 And Body Ground
    G05458090Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  -Repair short in the wire between the ECM/PCM (E16) and the SRS unit, the DLC.

    NO  -Update the ECM/PCM if it does not have the latest software (see UPDATING THE ECM/PCM ), 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  ).

NOTE: Before you begin, make sure the HDS and its DLC cable are working properly.
  1. Turn the ignition switch OFF.
  2. Connect the HDS to the DLC (see GENERAL TROUBLESHOOTING INFORMATION ).
    NOTE: Make sure the HDS is properly connected to the DLC.
  3. Turn the ignition switch ON (II), and read the HDS.

    Does the HDS identify the vehicle? 

    YES  -Go to step 4.

    NO  -Go to step  20.

  4. Check for Temporary DTCs or DTCs in the PGM-FI system with the HDS.

    Are any Temporary DTCs or DTCs indicated? 

    YES  -Go to the indicated DTCs troubleshooting.

    NO  -Go to step 5.

  5. Turn the ignition switch OFF.
  6. Turn the ignition switch ON (II), and watch the SRS indicator.

    Does the SRS indicator stay on? 

    YES  -Go to the SRS system's general troubleshooting information (see GENERAL TROUBLESHOOTING INFORMATION ).

    NO  -Go to step 7.

  7. Turn the ignition switch OFF.
  8. Turn the ignition switch ON (II), and watch the TPMS indicator.

    Does the TPMS indicator stay on? 

    YES  -Go to the TPMS system's general troubleshooting information (see GENERAL TROUBLESHOOTING INFORMATION ).

    NO  -Go to step 9.

  9. Turn the ignition switch OFF.
  10. Turn the ignition switch ON (II), and watch the VSA indicator.

    Does the VSA indicator stay on? 

    YES  -Go to the VSA system's general troubleshooting information (see GENERAL TROUBLESHOOTING INFORMATION ).

    NO  -Go to step 11.

  11. Turn the ignition switch OFF.
  12. Turn the ignition switch ON (II), and watch the immobilizer indicator.

    Does the immobilizer indicator stay on or flash? 

    YES  -Go to the immobilizer system's troubleshooting (see SYMPTOM TROUBLESHOOTING USING THE IMMOBILIZER INDICATOR LIGHTING PATTERN ).

    NO  -Go to step 13.

  13. Check for B-CAN system DTCs without the HDS (see TROUBLESHOOTING - B-CAN SYSTEM DIAGNOSIS TEST MODE 1 AND TEST MODE 2 (WITHOUT THE HDS) ).

    Are any B-CAN DTCs indicated? 

    YES  -Go to the indicated DTCs troubleshooting.

    NO  -Go to step 14.

  14. Turn the ignition switch OFF.
  15. Disconnect the HDS from the DLC.
  16. Check for continuity between body ground and DLC terminals No. 1 and No. 7 individually.
    Fig 2: Checking Continuity Between Body Ground And DLC Terminals No. 1 And No. 7 Individually
    G05458091Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  -Go to step 17.

    NO  -Go to step  18.

  17. Continue to check for continuity between DLC terminals No. 1 and No. 7 and body ground individually, while disconnecting these parts, one at a time:
    • SRS unit connector A (28P)
    • VSA modulator-control unit 37P connector
    • Immobilizer control unit 7P connector
    • TPMS control unit connector B (20P)
      Fig 3: Checking Continuity Between DLC Terminals No. 1 And No. 7 And Body Ground
      G05458092Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Does continuity go away when one of the above components is disconnected? 

    YES  -Replace the part that caused an open when it was disconnected.

    NO  -Repair short in the wire between the DLC No. 7 (K-line) and the VSA modulator-control unit, the SRS unit, the audio unit, or the TPMS control unit or DLC No. 1 (DIAG-H line) and the immobilizer control unit.

  18. Connect DLC terminals No. 1 and No. 7 to body ground with a jumper wire.
    Fig 4: Connecting DLC Terminals No. 1 And No. 7 To Body Ground With Jumper Wire
    G05458093Courtesy of AMERICAN HONDA MOTOR CO., INC.
  19. Check for continuity between body ground and these connector terminals:
    DLC TERMINAL DESCRIPTION

    Connector Unit Terminal DLC Terminal
    VSA modulator-control unit 37P No. 26 (LT BLU) No. 7 (LT BLU)
    SRS unit connector A 28P No. 24 (LT BLU) No. 7 (LT BLU)
    TPMS control unit connector B 20P No. 9 (LT BLU) No. 7 (LT BLU)
    Immobilizer control unit 7P No. 3 (GRY) No. 1 (GRY)

    Is there continuity between the DLC terminal and each of the terminals in the chart? 

    YES  -Replace the unit that does not communicate with the HDS.

    NO  -Repair open in the wire between the DLC (K-line or DIAG-H line) and the appropriate connector.

  20. Check for B-CAN system DTCs without the HDS (see TROUBLESHOOTING - B-CAN SYSTEM DIAGNOSIS TEST MODE 1 AND TEST MODE 2 (WITHOUT THE HDS) ).

    Is DTC B1168, B1169, and/or B1178 indicated? 

    YES  -Go to step  34.

    NO  -Go to step 21.

  21. Turn the ignition switch OFF.
  22. Disconnect the HDS from the DLC.
  23. Measure voltage between DLC terminal No. 16 and body ground.
    Fig 5: Measuring Voltage Between DLC Terminal No. 16 And Body Ground
    G05458094Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there battery voltage? 

    YES  -Go to step 24.

    NO  -Repair open in the wire between DLC terminal No. 16 and the No. 8 FI ECU (ECM/PCM) (15 A) fuse in the under-hood fuse/relay box.

  24. Measure voltage between DLC terminals No. 4 and No. 16.
    Fig 6: Measuring Voltage Between DLC Terminals No. 4 And No. 16
    G05458095Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there battery voltage? 

    YES  -Go to step 25.

    NO  -Repair open in the wire between DLC terminal No. 4 and G501.

  25. Connect the HDS to the DLC (see GENERAL TROUBLESHOOTING INFORMATION ).
  26. Jump the SCS line with the HDS.
  27. Disconnect ECM/PCM connector E (31P).
  28. Disconnect the HDS from the DLC.
  29. Connect DLC terminal No. 6 to body ground with a jumper wire.
    Fig 7: Connecting DLC Terminal No. 6 To Body Ground With Jumper Wire
    G05458096Courtesy of AMERICAN HONDA MOTOR CO., INC.
  30. Check for continuity between ECM/PCM connector terminal E15 and body ground.
    Fig 8: Checking Continuity Between ECM/PCM Connector Terminal E15 And Body Ground
    G05458097Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  -Go to step 31.

    NO  -Repair open in the wire between the ECM/PCM (E15) and DLC terminal No. 6.

  31. Disconnect the jumper wire.
  32. Connect DLC terminal No. 14 to body ground with a jumper wire.
    Fig 9: Connecting DLC Terminal No. 14 To Body Ground With Jumper Wire
    G05458098Courtesy of AMERICAN HONDA MOTOR CO., INC.
  33. Check for continuity between ECM/PCM connector terminal E26 and body ground.
    Fig 10: Checking Continuity Between ECM/PCM Connector Terminal E26 And Body Ground
    G05458099Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  -Update the ECM/PCM if it does not have the latest software (see UPDATING THE ECM/PCM ), 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 open in the wire between the ECM/PCM (E26) and DLC terminal No. 14.

  34. Try to start the engine.

    Does the engine start and idle smoothly? 

    YES  -Go to the F-CAN circuit troubleshooting (see F-CAN CIRCUIT TROUBLESHOOTING  ).

    NO  -Go to step 35.

  35. Turn the ignition switch OFF.
  36. Check the No. 23 +B IG1 MAIN (50 A) fuse in the under-hood fuse/relay box.

    Is the fuse OK? 

    YES  -Repair open in the wire between the No. 23 +B IG1 MAIN (50 A) fuse and the ignition switch. If the wire is OK, go to DLC circuit troubleshooting (part 2) (see DLC CIRCUIT TROUBLESHOOTING (PART 2)  ).

    NO  -Repair short in the wire between the No. 23 +B IG1 MAIN (50 A) fuse and the ignition switch. Also replace the No. 23 +B IG1 MAIN (50 A) fuse.

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