Honda S2000 Immobilizer

Honda S2000





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.

The vehicle has two kinds of keys.

• The black master key for:
  • ignition switch.
  • door locks.
  • trunk lock.
• The gray valet key for:
  • ignition switch.
  • door locks.

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.

• The immobilizer system can store up to six key codes.
• If it is necessary to rewrite the ECM, the dealer needs the customer's vehicle, all its master keys and valet keys, and the HDS equipped with an immobilizer program card with the latest version of HDS software. Any key that is not learned during rewriting will no longer start the engine, except keys duplicated with the Ilco Code Key Duplicator.
• If the customer has lost his key, and cannot start the engine, contact Honda Customer Relations.
• It is possible to add ONE new key without reprogramming all of the keys (follow the prompts in the HDS IMMOBI menu).

• If the proper key has been used, the immobilizer indicator light will come on for about 2 seconds, then go off.
• If the wrong key has been used or the code was not received or recognized by the ECM, the indicator light will come on for about 2 seconds, then it will blink until the ignition switch is turned OFF. For accurate immobilizer system diagnosis, get as much information from the customer as possible. A blinking indicator light means the key was not recognized.
• If the ignition switch is turned OFF, the indicator will blink for about 5 seconds to signal that the immobilizer system has been set correctly, then the indicator will go off.

Large metal objects, key fobs, other immobilizer keys, and other transponders can interfere with the immobilizer signal. If an intermittent problem is suspected, remove the ignition key from the key ring.

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CIRCUIT DIAGRAM

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TROUBLESHOOTING

Follow this procedure if the vehicle does not start, or after rewriting the ECM with the HDS and the vehicle does not start.

NOTE THESE ITEMS BEFORE TROUBLESHOOTING:

• Due to the action of the immobilizer system, the engine takes slightly more time to start than 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, troubleshoot the system.

1. Using a scan tool, check for a Diagnostic Trouble Code (DTC)
2. Turn the ignition switch ON (II) with the proper key.
3. Check to see if the immobilizer indicator light comes on.
4. Disconnect the 5P connector from the immobilizer receiver unit.

5. Check for voltage between the No. 1 terminal and body ground with the ignition switch turned ON (II).

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

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

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

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IMMOBILIZER RECEIVER UNIT REPLACEMENT

1. Remove the steering column covers.
2. Disconnect the 5P connector from the immobilizer receiver unit.

3. Disconnect the 7P connector from the ignition key switch.
4. Remove the four screws, and remove the immobilizer receiver unit from the ignition key cylinder.
5. Install in the reverse order of removal.
6. After replacement, make sure the immobilizer indicator light blinks correctly.

The ECM does not need to be reprogrammed if only the receiver has been replaced.




Honda S2000 AP1

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