GM Service Manual Online
For 1990-2009 cars only

When armed, the content theft deterrent (CTD) system is designed to deter vehicle content theft by pulsing the horns and exterior lamps for approximately 30 seconds when an unauthorized vehicle entry is detected. However, the CTD system does not affect engine starting.

An unauthorized entry can be any of the following with the CTD system armed:

    • When any door or the rear compartment is opened without first being unlocked using the keyless entry transmitter
    • After a battery reconnect, if the battery was disconnected with the CTD system armed
    • When the hood is opened (RPO UA2)

The components of the system are:

    • Body control module (BCM)
    • Remote control door lock receiver (RCDLR)
    • Security indicator
    • Door ajar switches
    • Rear compartment lid ajar switch
    • Hood ajar switch (RPO UA2)
    • Intrusion sensor (RPO UA2)
    • Intrusion sensor defeat switch (RPO UA2)
    • Theft deterrent alarm siren (RPO UA2)

Arming the CTD System

Use the following procedure in order to arm the system:

  1. Place the shift lever in PARK.
  2. Turn OFF the ignition.
  3. Open and close any door.
  4. Lock the doors with the LOCK button on the transmitter. The system is in standby mode and will not start the arming timer until all doors are closed.
  5. The system will begin the arm sequence immediately after the last door is closed. If the keyless entry transmitter is used to arm the system after the vehicle doors are closed, the arm sequence will begin as soon as the LOCK command is received by the transmitter. If selected through vehicle personalization, passive CTD arming may be selected.

Locking The Vehicle Without Arming The CTD System

Locking the vehicle may be accomplished without arming the CTD system. Use of the manual door locks will lock the vehicle, but will not arm the CTD system.

Disarming An Armed System/Silencing An Alarm

If system arming has occurred, it must be disarmed.

Important: Using the power door unlock switch or manually unlocking the doors does not disable the CTD arm mode. Also, disconnecting the battery or pulling fuses does not disable the arm mode, since the BCM stores the CTD mode status in memory.

To disarm the CTD system, perform one of the following:

    • Press the UNLOCK button on the transmitter.
    • Enter the vehicle passively with a correct key fob.

CTD Component Description

The following is a description of each component used in the CTD system:

Body Control Module (BCM)

The CTD system is an internal function of the BCM which utilizes serial data and various switch inputs to perform CTD functions. When the BCM detects an unauthorized entry, it activates the horns and exterior lamps for 30 seconds. The system will re-arm immediately following an alarm event.

Remote Control Door Lock Receiver (RCDLR)

The RCDLR receives input from the keyless entry transmitter, transferring information to the BCM via serial data. The BCM uses this information along with other information for activation and deactivation of the CTD system.

Security Indicator

The security indicator is illuminated by the instrument panel cluster (IPC) based on information, via serial data, from the BCM for CTD or from the theft deterrent module (TDM) for immobilizer. The CTD system uses the security indicator to inform the driver of system status prior to arming.

Door Ajar Switches

The CTD system uses the door ajar switches as a status indicator to activate the alarm. The BCM receives the status of the front door ajar switches based on a discrete input from each front door ajar switch. If the BCM receives a signal indicating a door is opened when the CTD system is armed, the BCM activates the alarm.

Rear Compartment Lid Ajar Switch

The CTD system uses the rear compartment lid ajar switch as a status indicator to activate the alarm. The rear compartment lid ajar switch is monitored by the BCM via a discrete input from the switch. When the CTD system is armed and the keyless entry transmitter is not used to open the rear compartment, the alarm will activate.

Hood Ajar Switch (RPO UA2)

The CTD system uses the hood ajar switch as a status indicator to activate the alarm. The BCM monitors the hood ajar switch via a discrete input from the switch. If the BCM receives a signal indicating the hood has been opened when the CTD system is armed, the BCM activates the alarm.

Inclination Sensor (RPO UA2)

The intrusion sensor is monitored by the BCM. The intrusion sensor is a motion sensor which monitors movement within the vehicle. If the CTD is in the armed mode and vehicle intrusion is detected, CTD will enter the alarm mode.

Theft Deterrent Alarm Siren (RPO UA2)

The theft deterrent alarm is a theft deterrent sounder. If the CTD System is in the alarm mode, the BCM will request the theft deterrent alarm ON.

Inputs

The BCM monitors the following inputs for CTD:

    • Door ajar switches
    • Keyless entry transmitter LOCK/UNLOCK buttons; a serial data message from the RCDLR
    • Immobilizer status--The BCM uses the immobilizer status for disarming the system or silencing an alarm when the correct vehicle key is used to start the vehicle.
    • Rear compartment lid ajar switch
    • Hood ajar switch (RPO UA2)
    • Intrusion sensor (RPO UA2)

Outputs

The body control module (BCM) controls he following outputs:

    • The horn relay
    • The exterior lamps
    • The theft deterrent alarm siren (RPO UA2)