Ignition Key (Transponder)
The ignition key for VTD equipped vehicles is a typical ignition key
with a transponder pellet located in the plastic end of the key. The ignition
key transponder value is used to determine if a valid ignition key
is being used to start the vehicle, there are approximately three trillion
different transponder values available. This vehicle has two types
of ignition keys.
| • | Master key (black plastic end) which can start the vehicle and
lock/unlock all door locks, all storage compartments and the rear compartment
lid lock. |
| • | Valet key (gray plastic end) which can start the vehicle and unlock/lock
all doors, but can not unlock/lock the storage compartments, or rear compartment
lid lock. |
Important: The transponder values are not readable and can not be serviced separately.
Reader Exciter
The Reader Exciter is part of the ignition lock cylinder. The following
inputs/outputs are all supplied by the VTD module:
| • | Battery voltage, CKT1459 (WHT). |
| • | Sensor signal, CKT 1836 (YEL). |
| • | Sensor return, CKT 1835 (BLK). |
Theft Deterrent (VTD) Module
The VTD module contains the software for controlling the VTD system.
The VTD module uses the following inputs and outputs to control the VTD
system.
Inputs
| • | Battery voltage from the underhood junction block IP fuse, CKT
240 (ORN). |
| • | Ignition start voltage from the ignition switch, CKT 1390 (WHT). |
| • | Ground, CKT 451 (BLK/WHT). |
Outputs
| • | Battery voltage to the Reader Exciter, CKT 1459 (WHT). |
| • | Sensor signal to the Reader Exciter, CKT 1836 (YEL). |
| • | Sensor return to the Reader Exciter, CKT 1835 (BLK). |
| • | Password exchange with the PCM (fuel enable), class 2 message. |
Powertrain Control Module (PCM)
The PCM verifies that the passwords received from the VTD module via
the class 2 serial data line are valid. If a password is invalid the PCM
disables the fuel delivery system. If the password is valid the PCM
enables the fuel delivery system, and the starter relay.
Starter Relays
The starter relay is controlled by the PCM module via the starter enable
control CKT 447 (YEL). If the PCM receives the correct password from the
VTD module, the PCM module switches the starter enable control CKT 447
(YEL) to ground. The relay is energized if the ignition switch is in the
START position and the gear selector is in the PARK or NEUTRAL positions.
