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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 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 ASSEMBLY REPLACEMENT ).
  11. Check for continuity between the immobilizer control unit-receiver 7P connector No. 5 terminal and body ground.
    Fig 1: Checking Continuity Between Immobilizer Control Unit-Receiver Connector Terminal 5 And Body Ground
    G03642269Courtesy 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) Body Ground
    G03642270Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there battery voltage? 

    1. YES  - Go to step 16.
    2. NO  - Faulty No. 13 (7.5 A) fuse in the passenger's under-dash fuse/relay box. If the fuse is OK, check for an open in the wire between the immobilizer control unit-receiver and passenger's under-dash fuse/relay box.
  16. Remove the gauge control module and disconnect its connectors (see GAUGE ASSEMBLY REPLACEMENT ).
  17. Check for continuity between the immobilizer control unit-receiver 7P connector No. 5 terminal and gauge assembly connector B (30P) No. 9 terminal.
    Fig 3: Checking Continuity Between Immobilizer Control Unit-Receiver 7P Connector Terminal 5 And Gauge Assembly Connector B (30P) Terminal 9
    G03642271Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    1. YES  - Faulty immobilizer indicator, replace the gauge assembly.
    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 terminal and body ground.
    Fig 4: Checking Voltage Between Immobilizer Control Unit-Receiver 7P Connector Terminal 6 And Body Ground
    G03642272Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there battery voltage? 

    1. YES  - Go to step 22.
    2. NO  - Faulty No. 92 (7.5 A) in the auxiliary fuse holder 2. If the fuse is OK, check for an open in the wire between the immobilizer control unit-receiver and auxiliary fuse holder 2.
  22. Turn the ignition switch OFF.
  23. Check for voltage between the immobilizer control unit-receiver 7P connector No. 1 and No. 6 terminals.
    Fig 5: Checking Voltage Between Immobilizer Control Unit-Receiver Connector Terminals 1 And 6
    G03642273Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there battery voltage? 

    1. YES  - Substitute a known-good immobilizer control unit-receiver and recheck.
    2. NO  - Repair an open in the wire or poor ground (G101).
  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 to symptom troubleshooting (see SYMPTOM TROUBLESHOOTING INDEX ).
    2. NO  - Go to step 28.
  28. Verify the System Check display on the HDS for the following information:
    • Harness short from the PCM to the immobilizer unit. (S-net line short)
    • The communication was not good between the PCM and the immobilizer unit by the battery voltage low.
    • The communication was not good between the immobilizer unit and the PCM by influence of some noise.
    • Immobilizer unit failure
    • 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. Disconnect the PCM connector B (56P).
  32. Check for continuity between the immobilizer control unit-receiver 7P connector No. 2 terminal and body ground.
    Fig 6: Checking Continuity Between Immobilizer Control Unit-Receiver 7P Connector Terminal 2 And Body Ground
    G03642274Courtesy 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 PCM.
  33. Verify the System Check display on the HDS for the following information:
    • Blown fuse
    • Harness open from the PCM and the immobilizer unit.
    • The communication was not good between the PCM and the immobilizer unit by battery voltage low.
    • The communication was not good between the immobilizer unit and the PCM by influence of some noise.
    • Immobilizer unit failure
    • 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. Disconnect the PCM connector B (56P).
  37. Connect the immobilizer control unit-receiver 7P connector No. 2 terminal and body ground with a jumper wire.
    Fig 7: Connecting Immobilizer Control Unit-Receiver Connector Terminal 2 And Body Ground With Jumper Wire
    G03642275Courtesy of AMERICAN HONDA MOTOR CO., INC.
  38. Check for continuity between the PCM connector B (56P) No. 41 terminal and body ground.
    Fig 8: Checking Continuity Between PCM Connector B (56P) Terminal And Body Ground
    G03642276Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

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