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For 1990-2009 cars only

Vehicle Theft Deterrent (VTD) Operation Domestic

The design of the passlock™ system is to prevent the vehicle operation if the proper ignition key is not used in order to start the vehicle. The mechanical key, in normal operation, will turn the passlock™ lock cylinder. The passlock™ sensor will relay the passlock™ data to the passlock™ module. The passlock™ module will determine the validity of the passlock™ data. The passlock™ module will send a code password to the vehicle/powertrain control module (VCM/PCM). When the VCM/PCM receives the correct code the VCM/PCM allows the fuel injectors to operate normally. The passlock™ system requires the VCM/PCM and the passlock™ module to communicate the various functions in order to operate. These functions transmit over the class 2 serial data line CKT 1807. For an explanation of the class 2 serial data operation refer to Data Link Communications Circuit Description in Wiring Systems

Vehicle Theft Deterrent (VTD) Operation Export

Lock and Unlock Commands

The VIM contains a radio receiver which is synchronized with the transmitter in the key fob (up to 4). The transmitter sends an RF signal with an identifier consisting of the following codes and message:

    • A fixed code--Sent in order to identify the fob as valid for the vehicle.
    • A variable code--Used in order to prevent the transmitter message from being recorded and to gain unauthorized access.
    • A message indicating the status of the LOCK/UNLOCK buttons-- Indicates the requested function (lock/unlock).

The VIM will ignore received transmissions in the following situations:

    • The fixed code portion of the identifier is not valid.
    • The message portion indicates both lock and unlock functions are being requested.
    • The variable code portion of the identifier does not match the value stored in the VIM.

When the UNLOCK button on a valid fob is pressed once within a range of the vehicle in a 15 second period and ignition 1 (start or RUN) is not present at the VIM the following events occur:

    • The left door is unlocked.
    • The following lamps flash once for 250 msec:
      • The turn signals
      • The front park lamps
      • The front repeater lamps
    • The immobilization function will be disabled for 2 minutes then enabled. Allow the engine to run.
    • The dome lamps and the courtesy lamps are illuminated for 40 seconds. If a door is opened during the 40 second delay, the control is based upon the door jamb switch input unless the dome lamp defeat switch is active.
        Whenever ignition 1 is detected at the VIM, the VIM will disable the interior lights output unless the door jamb switch input indicates a door is open.

When the UNLOCK button on a valid fob is pressed twice within range of the vehicle in a 15 second period and ignition 1 (START or RUN) is not present at the VIM, the following events will occur:

    • All events listed for a single button press.
    • The following doors are unlocked:
      • The right door
      • The side door
      • The cargo doors, if equipped

When the UNLOCK button on a valid fob is pressed 3 times within range of the vehicle in a 15 second period, ignition 1 (START or RUN) is NOT present at the VIM, and the vehicle is in PARK or NEUTRAL the following events will occur:

    • All the events listed for a single button press.
    • All the events listed for the second button press.
    • The liftgate and dutch doors, if equipped are unlocked.

When the LOCK button on a valid fob is pressed within range of the vehicle the following events will occur:

    • All the doors are locked.
        Note: If the side door is open at this time, the side door will not lock until commanded to do so by the door lock control module.
    • The following lamps will flash 3 times:
      • The turn signals
      • The front park lamps
      • The front repeater lamps
      • They are flashed ON for 250 msec and OFF for 100 msec.
    • The immobilization function is enabled without a time delay.
    • The dome lamps and courtesy lamps are illuminated for 2 seconds.
        Note: If any door is opened, the 2 second illuminate will delay until all the doors are closed unless the dome lamp defeat switch is active.

The VIM will also react to lock/unlock signals from the power door lock switches. The circuits used by the VIM to lock/unlock the doors are also used by the VIM in order to monitor the state of these circuits.

When the UNLOCK switch of any power door lock switch is activated the following events will occur:

    • All the doors are unlocked.
    • The following lamps are illuminated for 40 seconds:
      • The dome lamps
      • The courtesy lamps
      • If a door is opened during the 40 second delay, the control is based upon the door jamb switch input unless the dome lamp defeat switch is active.
    • Whenever ignition 1 is detected at the VIM, the VIM will disable its interior lights output unless the door jamb switch input indicates a door is open and the dome lamp defeat switch is not active.
    • The immobilizer function retains its subsequent status.

When the LOCK switch of any power door lock switch is activated, the following events will occur:

    • All the doors are locked.
        Note: If the side door is opened at this time, the side door will not lock until commanded to do so by the door lock control module.
    • The following lamps are illuminated for 2 seconds as long ignition 1 is off and the door jamb switch input is not active:
      • The dome lamps
      • The courtesy lamps
    • The immobilizer function retains its subsequent status.