Immobilizer System Troubleshooting

Before troubleshooting the immobilizer system, troubleshoot any ECM/PCM with diagnostic trouble codes (DTCs),and make sure the ECM/PCM has no malfunction.

Note these items before troubleshooting:

  • Due to the action of the immobilizer system, the engine takes slightly more time to start than on a vehicle without an immobilizer system.
  • When the system is normal, and the proper key is inserted, the indicator light comes on for 2 seconds, then it will go off.
  • If the indicator starts to blink after 2 seconds, or if the engine does not start, repeat the starting procedure.
    If the engine still does not start, continue with this procedure.

1.Turn the ignition switch ON (II) with programmed key.

2.Check to see if the immobilizer indicator light comes on.

Does the indicator light blink?


YES - Go to 3.


NO - Check for these problems:n

  • Blown No. 9 (10A) fuse in the under-hood fuse/relay box.
  • An open in the BLU/ORN wire between the gauge assembly and the immobilizer control unit-receiver.
  • A faulty immobilizer indicator light.
  • An open in the WHT/RED wire between the gauge assembly and the under-hood fuse/relay box.

3.Remove the steering column covers.

4.Disconnect the 7P connector from the immobilizer control unit-receiver.

 

5.Check for voltage between the immobilizer control unit-receiver 7P connector No. 7 terminal and body ground.

Is there battery voltage?


YES - Go to 6.


NO - Check for these problems:n

  • Blown No. 9 (10A) fuse in the under-hood fuse/relay box.
  • An open in the WHT/RED wire.

6.Check for voltage between the immobilizer control unit-receiver 7P connector No. 6 terminal and body ground with the ignition switch 0N (II).

Is there battery voltage?


YES - Go to 7.


NO - Check for these problems:

  • Blown No. 6 (15A) fuse in the under-hood fuse/relay box.
  • Faulty PGM-FI main relay 1.
  • An open in the YEL/BLK wire.

7.Check for voltage between the immobilizer control-unit receiver 7P connector No. 4 terminal and body ground with the parking brake lever pulled, then released.

Is there 1 V or less, then 5 V or more?


YES - Go to 8.


NO - Check for these problems:n

  • Faulty parking brake switch or a poor body ground of the parking brake switch.
  • Faulty brake fluid level switch.
  • An open in the GRN/RED wire.

8.Check for continuity between the immobilizer control unit-receiver 7P connector No. 1 terminal and body ground.

Is there voltage?


YES - Go to 9.


NO - Check for these problems:n

  • Poor ground (G101).
  • Faulty ECM/PCM.
  • An open in the BRN/YEL wire.

9.Check for continuity between the immobilizer control unit-receiver 7P connector No. 2 terminal and ECM/PCM terminal E27.

Is there continuity?


YES - Go to 10.


NO - Repair open in the WHT wire.n


10.Disconnect the negative cable from the battery.

11.Disconnect the ECM/PCM connector E.

12.Check for continuity between the immobilizer control unit-receiver 7P connector No. 2 terminal and body ground.

Is there continuity?


YES - Repair short to ground in the WHT wire.n


NO - Go to 13.


13.Check for continuity between the immobilizer control unit-receiver 7P connector No. 4 terminal and the multiplex control unit (under-dash fuse/relay box connector terminal C3).

Is there continuity?


YES - Replace the immobilizer control unit-receiver. After replacing the immobilizer control unit-receiver, rewrite the unit with a Honda PGM- Tester.n


NO - Repair open in the WHT wire. If the harness is OK, check to see if there is any Diagnostic Trouble Code (DTC) for the multiplex control unit. If it is, troubleshoot the multiplex control unit, then recheck.n