B2780

CIRCUIT DESCRIPTION
The instrument panel cluster (IPC) supplies a 5 volt signal and a ground circuit for the PASS-Key(R) system. This allows the IPC to detect PASS-Key(R) resistance values. Inserting the PASS-Key(R), with resistor pellet, in the ignition lock cylinder completes the PASS-Key(R) circuit. Contacts in the ignition lock cylinder mate with the pellet contacts. The IPC compares the resistance value of the key pellet to the valid resistance programmed into the IPC. If the proper resistance value is read, the IPC allows the engine to start. If the resistance value is incorrect, a malfunction is present and a DTC will set.

CONDITIONS FOR SETTING THE DTC
The IPC determines that one of the 15 valid key pellets was detected, but the current key pellet resistance value does not match the resistance of the one stored in the IPCs memory.

ACTION TAKEN WHEN THE DTC SETS
The IPC displays the STARTING DISABLED, DUE TO THEFT SYSTEM, REMOVE IGNITION KEY message on the driver message center and prevents the vehicle from starting. The IPC then starts the 3 minute delay sequence with messages.

CONDITIONS FOR CLEARING THE DTC
^ This DTC requires an ignition cycle in order to change from current to history.
^ The IPC detects a valid PASS-Key(R) resistance value on the PASS-Key(R) signal circuit.
^ A history DTC will clear after 100 consecutive ignition cycles if the condition for the malfunction is no longer present.
^ Use a scan tool.

DIAGNOSTIC AIDS
If this DTC is set as current, the vehicle ignition switch may have been tampered with. Ensure that all ignition keys for the vehicle are available and that every key sets the same malfunction DTC code.

TEST DESCRIPTION

Steps 1-5:

Steps 6-14:

The number below refers to the step number on the diagnostic table.
5. This test determines the key resistance code that is currently stored in the IPC memory.