Operation CHARM: Car repair manuals for everyone.

Antitheft and Alarm Systems: Testing and Inspection








The vehicle is equipped with an immobilizer system that will disable the vehicle unless the proper ignition key is used.

This system consists of a transponder located in the ignition key, an immobilizer receiver unit, an indicator light, and the ECM/PCM.

When the key is inserted in the ignition switch and turned to the (II) position, the immobilizer receiver unit sends power to the transponder in the ignition key. The transponder then sends a coded signal back through the immobilizer receiver unit to the ECM/PCM.

- The immobilizer system can store up to six key codes.
- If it is necessary to rewrite the ECM/PCM to learn a new key, the dealer needs the customer's vehicle, all its master keys and valet keys, and the Honda PGM Tester equipped with an immobilizer program card. Any key that is not learned during rewriting will no longer start the engine.
- If the customer has lost his key, and cannot start the engine, contact Honda Customer Relations.

Follow this procedure if the vehicle does not start after rewriting the ECM/PCM with the PGM-Tester.

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 two seconds, then it will go off.
- If the indicator starts to blink after two seconds, or if the engine does not start, repeat the starting procedure. If the engine still does not start, troubleshoot the system.
- If all the transponder and immobilizer receiver unit tests are OK, check the ECM/PCM.

If the ECM/PCM is faulty, substitute a known-good ECM/PCM, and recheck.

1. Using a scan tool. Check for a Diagnostic Trouble Code (DTC)

Is DTC P1607 indicated?
YES - Replace the ECM/PCM.
NO-Go to step 2.

2. Turn the ignition switch ON (II) with the proper key.

3. Check to see if the immobilizer indicator light flashes.

Does the indicator light blink?
YES - Go to step 4.
NO - Check for these problems:
- An open in the PNK wire between the gauge assembly and ECM/PCM.
- A faulty immobilizer indicator light.

4. Disconnect the 5P connector from the immobilizer receiver unit.

5. Check for voltage between the No.1 terminal and body ground.

Is there battery voltage?
YES - Go to step 6.
NO - Check for these problems:
- A blown fuse No.13 (15 A) in the under-dash fuse/relay box.
- A blown No.44 (15 A) fuse in the under-hood fuse/relay box.
- An open in the YEL/BLK wire between the PGM-FI main relay and the immobilizer receiver unit.

6. Check for continuity between the No.4 terminal and body ground.

Is there continuity?
YES - Go to step 7.
NO - Repair open in the BRN/BLK wire between the immobilizer receiver unit and G1O1.

7. Check for continuity between the No.2 terminal and the ECM/PCM.

Is there continuity?
YES - Go to step 8.
NO - Repair open in the RED wire between the immobilizer receiver unit and ECM/PCM.

8. Check for continuity between the No.3 terminal and ECM/PCM.

Is there continuity?
YES - Replace the immobilizer receiver unit.
NO - Repair open in the BLU wire between the immobilizer receiver unit and ECM/PCM.