Special Equipment Option (SEO) Vehicles (RPO 9C3, 9C6)

On SEO equipped vehicles, the key detection circuits (circuits 1073 and 1074 on non-SEO vehicles) are shorted together with a jumper circuit 1829. Since the key detection circuits are shorted together, the resistor sensing contacts in the ignition lock cylinder and the resistor pellet on the ignition key are no longer needed. This action causes the theft deterrent module to stay unprogrammed because it lacks the ability to read and store (program) a resistor pellet code.

An unprogrammed theft deterrent module performs the following actions:
^ Enables the theft deterrent relay by grounding circuit 625.
^ Sends a password to the PCM through circuit 229 to enable fuel delivery to the engine.
^ The engine will start.

The SECURITY indicator in the instrument cluster is not present. However, the theft deterrent module output to the SECURITY indicator (circuit 728) is sent to the Data Link Connector (DLC) terminal 8.

To verify that the theft deterrent module is unprogrammed:
1. Connect a test light between the Data Link Connector (DLC) terminals 8 and 16.
2. TURN the ignition switch to the RUN position.
3. Observe the test light:
^ A unprogrammed theft deterrent module will flash (on/off) the test light. The system is in good condition.
^ A programmed theft deterrent module will turn on steadily the test light. Replace the theft deterrent module. Refer to Theft Deterrent System for service procedures.

When replacing a theft deterrent module on a SEO equipped vehicle, it must remain unprogrammed. The key detection circuit wires (circuits 1073 and 1074 on non-SEO equipped vehicles) are shorted together with a jumper circuit 1829. Therefore, circuit 1829 prevents unnecessary theft deterrent module programming. If the theft deterrent module programs itself (see test above), check for excessive resistance in jumper circuit 1829.