Theft Deterrent Module

The theft deterrent module contains the software in order to do the following actions:
^ To monitor the inputs for the PASS-Key(R) II system
^ To control the outputs for the PASS-Key(R) II system

The following circuits are the theft deterrent module inputs:
^ The battery voltage (CKT 1642, RED) input to the module draws about 1 milliamp when the ignition is OFF.
^ The ignition voltage (CKT 139, PNK) input (Buick) is used to wake up the module. When you turn the ignition switch to the RUN position, the module continuously measures the ignition key resistor. When the ignition switch is in OFF, LOCK or ACCY, the module does not measure the ignition key resistor.
^ Ground (CKT 251, BLK/WHT)
^ The key resistor (CKT 1073, WHT/BLK) and the key resistor ground (CKT 1074, PPL/WHT) inputs are used to determine if you are using the correct key in order to start the vehicle.

The following circuits are the theft deterrent module outputs:
^ The theft deterrent module (CKT 625, YEL/BLK) output controls the theft deterrent relay.
^ The fuel enable (CKT 229, DK BLU) output commands the PCM in order to enable the fuel delivery. When the theft deterrent module sees the proper ignition key resistance, the module sends a Pulse Width Modulated (PWM) signal to the PCM. If the theft deterrent module does not see the proper ignition key resistance, the module does not send a PWM signal to the PCM.
^ The SECURITY indicator (CKT 264, DK GRN) output controls the indicator that is located within the instrument cluster.