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For 1990-2009 cars only

Content Theft Deterrent (CTD) System

The theft deterrent system on this vehicle is comprised of 2 separate systems. The systems are the PASSLOCK® system and the content theft deterrent (CTD) system. There are separate description and diagnosis procedures within this section. The CTD function provides the theft deterrent by sounding the horn and flashing the headlamps and the parklamps when there is an unauthorized vehicle entry or there is tampering detected.

Body Control Module (BCM)

The body control module (BCM) monitors several inputs in order to arm and disarm the CTD system. The BCM controls the alarm function outputs. When the BCM detects an unauthorized entry (any door opened), the BCM applies ground to the horn, the park lamp and the headlamp relays. The BCM will send messages to the security indicator in the instrument cluster through the Class 2 serial data link. The BCM has the following 8 basic modes for operating the CTD system. The more detailed descriptions are below.

    • Off state
    • Idle state
    • Disarmed state
    • Ready-to-arm state
    • Arm initiated state
    • Arm delay state
    • Armed state
    • Alarm state

The BCM has the following 6 discrete inputs in order to monitor the CTD system:

    • Ignition 1
    • Driver door mini-wedge (door jamb) switch
    • Passenger door mini-wedge (door jamb) switch
    • Door lock relay
    • Door key switch
    • Passenger door unlock relay

The BCM applies ground once per second for approximately 2 minutes, or until a valid input to disarm the system is received by the BCM.

Door Mini-Wedge (Door Jamb) Switches

The theft deterrent system uses the door mini-wedge switch as one method in order to activate the alarm. If the BCM detects any door opening before the BCM receives a disarm input, the alarm mode activates.

Door Key Switch

The BCM monitors the door key switches in order to disarm the CTD system. When the lock cylinder turns in order to unlock the door, the switch grounds the disarm input to the BCM.

Remote Control Door Lock Receiver Module System

The remote control door lock receiver module system may also arm and disarm the CTD system. When the remote control door lock receiver receives a door lock or an unlock signal from the key fob, the remote control door lock receiver sends a message to the BCM. The message orders the BCM to perform the appropriate door lock/unlock command. The BCM detects the message and performs one of the following functions:

    • Locks the doors and enters the armed initiated mode
    • Unlocks the doors and enters the ready-to-arm mode

Off State

The CTD system will be in the off state when the ignition switch is in the RUN position and all the doors are closed. The BCM will request the security indicator to remain OFF.

Idle State

The CTD system will be in the idle state when the ignition switch is in the RUN position and any door is open. The BCM will request the security indicator to remain OFF.

Disarmed State

The CTD system will be in the disarmed state when the ignition switch is in the LOCK (off) position and all the doors are closed. The BCM will request the security indicator to remain OFF.

Ready-To-Arm State

The CTD system will be in the ready-to-arm state when the ignition switch is in the LOCK (off) position and any door opens. The BCM will request the security indicator to flash.

Arm Initiated State

The CTD system will be in the arm initiated state when the ignition switch is in the LOCK (off) position, any door opens, and the BCM detects a lock command from either the power door lock switch or the remote control door lock receiver. The BCM will request the security indicator to remain ON.

Arm Delay State

The CTD system will enter the arm delay state when the ignition switch is in the LOCK (off) position, the BCM receives a LOCK command from either the power door lock switch or the remote control door lock receiver and all the doors are closed. The BCM will request the security indicator to remain ON for 15 seconds.

Armed State

The CTD system will enter the armed state after the 15 second delay of the arm delay state, unless the BCM detects any door opening within that time. The BCM monitors the inputs (listed above) in order to determine whether to activate the alarm or to disarm the system. The BCM will request the security indicator to remain OFF.

Alarmed State

The CTD system will enter the alarmed state from the armed state if any door opens. The horns and the exterior lights will alternate off and on for approximately two minutes or until an unlock command is received by the BCM. If the BCM does not receive an unlock command, the CTD system will go back to the armed state. The BCM will request the security indicator to remain off. The CTD system will change from the alarm state to the off state if the vehicle control module (VCM)/powertrain control module (PCM) receives a valid Passlock® ignition key rotation.

Remote Panic Alarm/Vehicle Locator State

The CTD system will enter the remote panic alarm/vehicle locator state when the panic button on the key fob is pressed. When the panic button is pressed, the remote control door lock receiver sends a message to the BCM. The BCM will sound the horns and flash the headlamps and the parklamps. You can disable the remote panic alarm/vehicle locator state by pressing the panic button on the key fob again or the system will time out after 30 seconds.