B2955

CIRCUIT DESCRIPTION
The Vehicle Theft Deterrent (VTD) controller module checks the theft deterrent exciter module key data signal circuit for a constant voltage condition.

CONDITIONS FOR RUNNING THE DTC
The VTD controller module must see the ignition switch input. The VTD controller module can not have DTC B1327 set as a current DTC.

CONDITIONS FOR SETTING THE DTC
The theft deterrent controller module requires 1 second to monitor the ignition key. After the first second, the theft deterrent controller module turns off the power to the theft deterrent exciter module. If the theft deterrent controller module senses the key data signal to the theft deterrent exciter module is 12 V for 1 second, the theft deterrent controller module sets this DTC.

ACTION TAKEN WHEN THE DTC SETS

IMPORTANT: If the theft deterrent controller (VTD) module senses the sensor low reference circuit is 12 volts after the vehicle has started, the VTD module will enter fail enable state. The vehicle will not stall or stop running. If the VTD module is in a fail enable state when the ignition is turned to OFF, it will remain fail enable until the next time the vehicle is started. If the VTD module is fail enabled, the Pass Key Ill system is NOT active and the vehicle will start.
^ Stores DTC B2955.
^ The vehicle will not start.
^ The VTD module sends a class 2 message to the instrument cluster to illuminate the SECURITY indicator.

CONDITIONS FOR CLEARING THE MIL/DTC
The theft deterrent controller module clears the current status of the DTC when it does not sense a 12 V condition on the theft deterrent exciter module key data signal circuit. The DTC will still be retrieved as current until the ignition switch is cycled. The DTC will become a history DTC at that time.

DIAGNOSTIC AIDS
Refer to Testing for Intermittent and Poor Connections and Testing for Electrical Intermittents in Diagrams.

TEST DESCRIPTION

Steps 1-8:

The numbers below refer to the step numbers on the diagnostic table.
2. Make sure the good ground used is separate from the grounds used by the vehicle theft deterrent module. Voltage measurement must not interfere with possible isolated module ground.