B2955

Diagnostic Chart:

SCHEMATIC
Refer to 160/310 Cell 133: Vehicle Theft Deterrent Module schematic

CIRCUIT DESCRIPTION
The vehicle theft deterrent (VTD) module checks the exciter/receiver key data signal circuit for a constant voltage condition.

CONDITIONS FOR RUNNING THE DTC
The VTD must see the ignition switch input. The VTD must have DTC B3055, Key Not Present, set as a current DTC. The VTD can not have a B1327 DTC set as a current DTC.

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

ACTION TAKEN WHEN THE DTC SETS
When the vehicle is running, the VTD will allow the vehicle to continue running. If the 12 V is detected on the key data signal circuit with the engine off, the VTD will prevent a start. The VTD will illuminate the security indicator.

CONDITIONS FOR CLEARING THE DTC
The VTD clears the current status of the DTC when it does not sense a 12 V condition on the exciter/receiver 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.

TEST DESCRIPTION
The numbers below refer to the step numbers on the diagnostic table.
1. Be sure that the original ignition key issued with the vehicle is used when performing the Vehicle Theft Deterrent Diagnostic System Check.
2. Make sure the ground used is separate from the grounds used by the vehicle theft deterrent module. Voltage measurement must not interfere with possible isolated module ground.