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Immobilizer System: Troubleshooting

  1. Turn the ignition switch ON (II) with a programmed key.
  2. Check to see if the immobilizer indicator comes on.

    Does the indicator come on? 

    1. YES  - Go to step 3.
    2. NO  - Go to step  12.
  3. Check the immobilizer indicator operation.

    Does the indicator come on for 2 seconds, then go off? 

    1. YES  - Go to step 4.
    2. NO  - Go to step  6.
  4. Try to crank the engine.

    Does the starter motor operate? 

    1. YES  - Go to step 5.
    2. NO  - Check the starter motor.
  5. Try to start the engine.

    Does the engine start? 

    1. YES  - If available, check the Status Log in the Immobilizer Info with the HDS (see STATUS LOG ). If the Status Log is not available, the immobilizer system is OK at this time.
    2. NO  - Go to step  24.
  6. Check to see if the immobilizer indicator comes on and blinks.

    Does the indicator blink? 

    1. YES  - Go to step  24.
    2. NO  - Go to step 7.
  7. Disconnect the 7P connector from the immobilizer control unit-receiver.
  8. Check to see if the immobilizer indicator goes off.

    Does the indicator go off? 

    1. YES  - Substitute a known-good immobilizer control unit-receiver and/or ECM/PCM.
    2. NO  - Go to step 9.
  9. Turn the ignition switch OFF.
  10. Remove the gauge control module, and disconnect its connectors (see GAUGE CONTROL MODULE REPLACEMENT ).
  11. Check for continuity between the immobilizer control unit-receiver 7P connector No. 5 (IMOARM) terminal and body ground.
    Fig 1: Checking Continuity Between Immobilizer Control Unit-Receiver 7P Connector Terminal 5 And Body Ground
    G03662299Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    1. YES  - Repair a short in the wire.
    2. NO  - Faulty immobilizer indicator, replace the gauge control module.
  12. Try to start the engine.

    Does the engine start? 

    1. YES  - Go to step 13.
    2. NO  - Go to step  18.
  13. Turn the ignition switch OFF.
  14. Disconnect the 7P connector from the immobilizer control unit-receiver.
  15. Check for voltage between the immobilizer control unit-receiver 7P connector No. 7 (+B) terminal and body ground.
    Fig 2: Checking Voltage Between Immobilizer Control Unit-Receiver 7P Connector Terminal 7 (+B) And Body Ground
    G03662300Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there battery voltage? 

    1. YES  - Go to step 16.
    2. NO  - Faulty No. 7 (7.5 A) fuse in the under-dash fuse/relay box. If the fuse is OK, check for an open in the wire between the immobilizer control unit-receiver and under-dash fuse/relay box.
  16. Remove the gauge control module and disconnect its 30P connector (see GAUGE CONTROL MODULE REPLACEMENT ).
  17. Check for continuity between the immobilizer control unit-receiver 7P connector No. 5 (IMOARM) terminal and gauge control module connector A (30P) No. 7 terminal.
    Fig 3: Checking Continuity Between Immobilizer Control Unit-Receiver 7P Connector Terminal 5 And Gauge Control Module Connector A (30P) Terminal 7
    G03662301Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    1. YES  - Faulty immobilizer indicator, replace the gauge control module.
    2. NO  - Repair an open in the wire.
  18. Turn the ignition switch OFF.
  19. Disconnect the 7P connector from the immobilizer control unit-receiver.
  20. Turn the ignition switch ON (II).
  21. Check for voltage between the immobilizer control unit-receiver 7P connector No. 6 (IG1) terminal and body ground.
    Fig 4: Checking Voltage Between Immobilizer Control Unit-Receiver 7P Connector Terminal 6 (IG1) And Body Ground
    G03662302Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there battery voltage? 

    1. YES  - Go to step 22.
    2. NO  - Faulty No. 19 (15 A) fuse in the under-dash fuse/relay box. If the fuse is OK, check for an open in the wire between the immobilizer control unit-receiver and under-dash fuse/relay box.
  22. Turn the ignition switch OFF.
  23. Check for continuity between the immobilizer control unit-receiver 7P connector No. 1 (LG1) terminal and body ground.
    Fig 5: Checking Continuity Between Immobilizer Control Unit-Receiver 7P Connector Terminal 1 (LG1) And Body Ground
    G03662303Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    1. YES  - Substitute a Known-good immobilizer control unit-receiver and/or ECM/PCM.
    2. NO  - Repair an open in the wire.
  24. Turn the ignition switch OFF.
  25. Connect the HDS to the data link connector.
  26. Turn the ignition switch ON (II).
  27. Look at the System Check in the Immobilizer Info with the HDS (see SYSTEM CHECK ).

    Is the immobilizer system normal? 

    1. YES  - Go back to step  1.
    2. NO  - Go to step 28.
  28. Verify the System Check display on the HDS for the following information:
    • Harness short from the ECM/PCM to the immobilizer control unit-receiver. (S-net, IMOCD-terminal short)
    • The communication was not good between the ECM/PCM and the immobilizer control unit-receiver by the battery voltage low.
    • The communication was not good between the immobilizer control unit-receiver and the ECM/ PCM by influence of some noise.
    • ECM/PCM failure

    Does the HDS display any of the above information? 

    1. YES  - Go to step 29.
    2. NO  - Go to step  33.
  29. Turn the ignition switch OFF.
  30. Disconnect the 7P connector from the immobilizer control unit-receiver.
  31. Short the SCS connector, then disconnect the ECM/ PCM connector A ('04-05 models) or E ('06 model) (31P) (see HOW TO UPDATE THE ECM/PCM ).
  32. Check for continuity between the immobilizer control unit-receiver 7P connector No. 2 (S-NET (IMOCD-TERMINAL)) terminal and body ground.
    Fig 6: Checking Continuity Between Immobilizer Control Unit-Receiver 7P Connector Terminal 2 (S-NET (IMOCD-TERMINAL)) And Body Ground
    G03662304Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    1. YES  - Repair a short in the wire.
    2. NO  - Substitute a known-good immobilizer control unit-receiver and/or ECM/PCM.
  33. Verify the System Check display on the HDS for the following information:
    • Blown fuse
    • Harness open from the ECM/PCM and the immobilizer control unit-receiver.
    • The communication was not good between the ECM/PCM and the immobilizer control unit-receiver by battery voltage low.
    • The communication was not good between the immobilizer control unit-receiver and the ECM/ PCM by influence of some noise.
    • Immobilizer control unit-receiver failure
    • ECM/PCM failure

    Does the HDS display any of the above information? 

    1. YES  - Go to step 34.
    2. NO  - Check the Possible Failures shown on the System Check display (see SYSTEM CHECK 
  34. Turn the ignition switch OFF.
  35. Disconnect the 7P connector from the immobilizer control unit-receiver.
  36. Short the SCS connector, then disconnect the ECM/ PCM connector A ('04-05 models) or E ('06 model) (31P) (see HOW TO UPDATE THE ECM/PCM ).
  37. Check for continuity between the immobilizer control unit-receiver 7P connector No. 2 (S-NET (IMOCD-TERMINAL) terminal and ECM/PCM connector A ('04-05 models) or E ('06 model) (31P) No. 25 terminal.
    Fig 7: Checking Continuity Between Immobilizer Control Unit-Receiver 7P Connector Terminal 2 (S-NET (IMOCD-TERMINAL) And ECM/PCM Connector A ('04-05 Models) Or Terminal 25 E ('06 Model) (31P)
    G03662305Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    1. YES  - Substitute a known-good immobilizer control unit-receiver and/or ECM/PCM.
    2. NO  - Repair an open in the wire.
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