GM Service Manual Online
For 1990-2009 cars only
Table 1: Theft Deterrent/Shock Sensor Modes
Table 2: Theft Deterrent Arm/Disarm Modes

The content theft deterrent system is designed to deter vehicle vandalism and theft. The content theft deterrent system is optional equipment (RPO UA6).

The content theft deterrent system performs the following functions:

    • Flashes the exterior lights
    • Sounds the horn

The content theft deterrent system may not be disarmed by removing the power or ground feeds to the body control module (BCM).

System Components

The content theft deterrent (CTD) system (UA6) contains the following components:

    • The body control module (BCM) type 4
    • The shock sensor
    • The door lock switches
    • The sliding door jamb switches
    • The theft deterrent relay
    • The security indicator lamp
    • The key cylinder lock switches
    • The keyless entry system
    • The power door lock switches

Body Control Module (BCM)

The body control module (BCM) type 4 controls the content theft deterrent system.

The BCM monitors the status of the following components:

    • The vehicle doors
    • The lock cylinders
    • The shock sensor
    • The power door locks
    • The keyless entry system

The BCM operates the following components according to the chosen mode of operation:

    • The exterior lights
    • The horn
    • The status security indicator lamp

Inspecting for the Correct BCM Type

Complete the following steps in order to determine the BCM type installed in the vehicle:

  1. Turn the ignition switch to the LOCK position.
  2. Remove the BCM PRGRM fuse.
  3. Turn the ignition switch to the ACC position.

The seat belt indicator flashes and the chime sounds 2, 3 or 4 times. The number of chimes indicates the BCM type that is installed in the vehicle.

Verify that a BCM type 4 is installed on a vehicle with the content theft deterrent option (RPO UA6). Refer to Service Parts ID Label and RPO Code List .

If the vehicle is RPO UA6 but is not equipped with BCM type 4, install a BCM type 4.

If the vehicle is not RPO UA6 and has a BCM type 4, refer to Diagnostic System Check - Body Control System

Door Key Cylinder Locks

The left front, right front, and liftgate door key cylinder locks have integral switches that signal the BCM to arm or disarm the theft deterrent system.

Security Indicator Lamp

The BCM controls the operation of the security indicator lamp. Based on the current system operating mode, the BCM may cause the security indicator lamp to operate in one of the following modes:

  1. On
  2. Off
  3. Flashing slow
  4. Flashing fast

Shock Sensor

The shock sensor sends a tamper (ground) signal to the BCM through CKT 1828 if an impact to the vehicle occurs which is in excess of the shock sensor pre-calibrated level.

Theft Deterrent Relay

The BCM controls the theft deterrent relay. The exterior lights turn on during certain modes of operation.

Arming

Complete the following steps in order to arm the content theft deterrent (CTD) system:

  1. Turn the ignition switch to the LOCK position.
  2. Remove the key from the ignition lock cylinder.
  3. Open the driver door.
  4. While the driver door is open, perform one of the following actions:
  5. • Press lock on either power door lock switch.
    • Press lock on the keyless entry transmitter.
    • Use the left front, right front, or liftgate door key cylinder in order to lock the door.

The security indicator lamp flashes while the driver door is open. The lamp lights steadily when the following conditions exist:

    • The driver side door is closed.
    • The content theft deterrent system enters the arming mode.

The lamp flashes continuously at a slow rate when the content theft deterrent system is armed.

Refer to Theft Deterrent Arm/Disarm Modes in this description for procedures on enabling or disabling the lock switch arming feature.

Disarming

Use either of the following steps in order to disarm the content theft deterrent system:

    • Unlock the left front, right front, or liftgate door by using the key in the key lock cylinder.
    • Press unlock on a keyless entry transmitter.

Refer to Theft Deterrent Arm/Disarm Modes in this description for procedures on enabling or disabling the lock cylinder disarming feature.

Alarm

The CTD activates the alarm when the system is armed and one of the following actions occurs:

    • A door opens.
    • You turn the ignition switch to the ACC or RUN position.
    • The vehicle is impacted in excess of the precalibrated level of the shock sensor.
    • You press ALARM on the keyless entry transmitter.

The CTD causes the following signals for 2 minutes during alarm mode:

    • The headlamps flash.
    • The horn sounds.

Refer to Theft Deterrent/Shock Sensor Modes in this description for procedures on enabling or disabling the shock sensor.

Warning

The CTD causes the following alternating actions when the shock sensor detects an impact to the vehicle:

    • The exterior lights flash 5 times.
    • The horn sounds for 2 minutes.

Refer to Theft Deterrent/Shock Sensor Modes in this description for procedures on adjusting the shock sensor sensitivity.

Operating Modes

The content theft deterrent system has the following operating modes:

    • The STAND BY mode
    • The LAMP FLASHING mode
    • The LAMP STEADY ON mode
    • The IGNITION ON mode
    • The DELAY mode
    • The ARMED mode
    • The RE-ARM WAIT mode
    • The WARNING mode
    • The ALARM mode

Stand-By Mode

Lamp status: Off

The content theft deterrent system enters the STAND BY mode when all of the following conditions exist:

    • The doors are unlocked in one of the following ways:
       - Pressing unlock on the keyless entry transmitter
       - Unlocking the left front, right front, or liftgate door using the door key cylinders when the arm/disarm is in mode 1 or 3
    • The ignition switch is in the OFF or LOCK position with the key fully inserted in the ignition key lock cylinder.
    • All of the vehicle doors are closed.

The content theft deterrent system exits the stand-by mode and goes into the IGNITION ON mode when you turn the ignition switch to the ACC or RUN position.

Lamp Flashing Mode

Lamp status: The lamp flashes for 10 minutes, then turns off. In vehicles with less than 15 total accumulated miles, the lamp flashes for 3 minutes.

The content theft deterrent system enters the LAMP FLASHING mode when all of the following conditions exist:

    • The key is removed from the ignition key lock cylinder.
    • Any door is open.
    • The doors are unlocked in one of the following ways:
       - Pressing unlock on the keyless entry transmitter
       - Unlocking the left front, right front, or liftgate door using the door key cylinders when the arm/disarm is in mode 1 or 3

The content theft deterrent system exits the LAMP FLASHING mode and goes into the IGNITION ON mode when you turn the ignition switch to the ACC or the RUN position.

Lamp On Steady Mode

Lamp status: The lamp is on for 10 minutes and then turns off. In vehicles with less than 15 total accumulated miles, the lamp turns on for 3 minutes.

The content theft deterrent system enters the LAMP ON STEADY mode when all of the following conditions exist:

    • The ignition switch is removed from the ignition key lock cylinder.
    • While any door is open, perform one of the following actions:
       - Press lock on either power door lock switch.
       - Press lock on the keyless entry transmitter.
       - Use the left front, right front, or liftgate door key cylinder in order to lock the door.

The content theft deterrent system exits the lamp on steady mode and goes into the IGNITION ON mode when you turn the ignition switch to the ACC or RUN position.

Ignition On Mode

Lamp status: Off

The content theft deterrent system goes into IGNITION ON mode when you turn the ignition switch to the ACC or RUN position during one of these modes:

    • Stand-by
    • Lamp flashing
    • Lamp on steady
    • Delayed

The content theft deterrent system stays in the IGNITION ON mode when the ignition switch is in the ACC or RUN position.

Delay Mode

Lamp status: On steady

The content theft deterrent system enters the DELAY mode when all of the following conditions exist:

    • The key is removed from the ignition key lock cylinder.
    • All of the doors are closed.
    • Pressing lock on the keyless entry transmitter, power door lock switch, or locking the left front, right front, or liftgate door using the key cylinder lock.

The BCM remains in delay mode for 1 second and then goes into armed mode.

The content theft deterrent system exits the delay mode and goes into the IGNITION ON mode when the ignition switch is turned to the ACC or RUN position.

Armed Mode

Lamp status: Flashes slowly

When the content theft deterrent system enters the ARMED mode, the BCM performs the following functions:

    • For remote activation verification in mode 3 or mode 4, the BCM sounds the horn for 23-27 ms. Refer to Keyless Entry System Description in Keyless Entry for more information about this mode.
    • For remote activation verification in mode 2, mode 3 or mode 4, the BCM flashes the exterior lights once after sounding the horn. Refer to Keyless Entry System Description in Keyless Entry for more information about this mode.

The content theft deterrent system stays in the armed mode until one of the following conditions exists:

    • Press LOCK on the keyless entry transmitter. The system goes into the STAND BY mode.
    • Unlock the doors using the left front, right front, or liftgate door key cylinder when the arm/disarm is in mode 1 or mode 3. The system goes into the STAND BY mode.
    • Open a vehicle door. The system goes into the ALARM mode.
    • Tampering with the rear compartment lock occurs. The system goes into the WARNING mode.
    • Trigger the shock sensor when the arm/disarm is in mode 1 or mode 3. The system goes into the ALARM mode.
    • Turn the ignition switch from the LOCK position to the ACC or RUN position. The system goes into the alarm mode.

Re-Arm Wait Mode

Lamp status: On steady

The BCM waits for all trigger inputs to clear before entering the RE-ARM wait mode after an alarm mode operation.

The content theft deterrent system stays in the RE-ARM wait mode for 2 seconds when all of the following conditions exist:

    • All of the vehicle doors remain closed.
    • The shock sensor is not triggered.
    • The ignition switch remains in the LOCK position.

After 2 seconds, the content theft deterrent system goes into the ARMED mode.

Warning Mode

Lamp status: On steady

The WARNING mode attempts to warn away potential intruders before the content theft deterrent system goes into the ALARM mode. The BCM flashes the exterior lights and sounds the horn alternately 5 times rapidly. Then the content theft deterrent system goes into the ARMED mode.

The content theft deterrent system remains in the WARNING mode until one of the following actions occurs:

    • Open a vehicle door. The system goes into the ALARM mode.
    • Trigger the shock sensor when the arm/disarm is in mode 1 or mode 3. The system goes into the ALARM mode.
    • Turn the ignition switch from the LOCK position to the ACC or RUN position. The system goes into the ALARM mode.
    • The content theft deterrent system has been in the WARNING mode 5 times. The system goes into the ALARM mode.

Alarm Mode

Lamp status: On steady

The BCM flashes the exterior lights and sounds the horn alternately for 2 minutes. The content theft deterrent system then enters the RE-ARM WAIT mode.

The content theft deterrent system stays in the ALARM mode until one of the following actions occurs:

    • Press UNLOCK on the keyless entry transmitter. The system goes into the STAND BY mode.
    • Unlock the doors using the left front, right front, or liftgate using the door key cylinder when the arm/disarm is in mode 1 or mode 3. The system goes into the STAND BY mode.
    • Press ALARM on the keyless entry transmitter. The system goes into the RE-ARM WAIT mode.

Shock Sensor Adjustment

  1. Turn the ignition switch to the LOCK position.
  2. Remove the left instrument panel sound insulator.
  3. Remove the BCM PRGRM fuse.
  4. Turn the ignition switch to the ACC position. The BCM flashes the fasten belts indicator and sounds the chime four times. This identifies that the BCM type 4 is installed on the vehicle.
  5. Within 1 second, turn the ignition switch from the ACC position, to the LOCK position, then back to the ACC position.
  6. Rotate the shock sensor adjustment knob counterclockwise in order to decrease the sensitivity level. Rotate the shock sensor adjustment knob clockwise in order to increase the sensitivity level.
  7. Rotate the shock sensor adjustment knob in 30 degree increments, then simulate a small vehicle impact. Choose an area of the vehicle such as the bumpers in order to avoid body damage.
  8. • Depending on the sensitivity level of the shock sensor and the magnitude of the impact, the horn sounds for 25 ms upon detecting a vehicle impact.
    • If the sensitivity level is high, the horn sounds for 100 ms upon detecting a vehicle impact.
  9. Repeat steps 6 and 7 until you reach the desired sensitivity level.
  10. Turn the ignition switch to the LOCK position.
  11. Reinstall the BCM PRGRM fuse.
  12. Install the left instrument panel sound insulator.

Theft Deterrent/Shock Sensor Modes

Mode 1:  If the shock sensor is triggered or any door is opened while the content theft deterrent system is armed, the horn sounds and the exterior lights flash for 2 minutes.

Mode 2: If any door is opened while the content theft deterrent system is armed, the horn sounds and the exterior lights flash for 2 minutes. The system ignores the shock sensor.

Mode 3: The content theft deterrent system stays disarmed at all times.

Mode 4: If any door is opened while the content theft deterrent system is armed, the horn sounds and the exterior lights flash for 2 minutes. If the shock sensor is triggered, the horn sounds and the exterior lights flash 5 times rapidly, then the system rearms. When the shock sensor is triggered 5 times, then the horn sounds and the exterior lights flash for 2 minutes.

Theft Deterrent/Shock Sensor Modes

Mode

Theft Deterrent

Shock Sensor

Warning

1

Enabled

Enabled

Disabled

2

Enabled

Disabled

Disabled

3

Disabled

Disabled

Disabled

4

Enabled

Enabled

Enabled

Theft Deterrent Arm/Disarm Modes

Important: Although mode 2 provides increased security, the content theft deterrent system disarms only by pressing unlock on the keyless entry transmitter. This can pose a problem if the keyless entry transmitter is damaged, lost, or inoperative for any reason while you attempt to disarm the content theft deterrent system.

Mode 1: The system arms when you lock the doors with the keyless entry transmitter. The system disarms when you unlock the left front, right front, or liftgate door with the key or the keyless entry transmitter. The system does not arm when you lock the doors with a power door lock switch.

Mode 2: The system arms when you lock the doors with the keyless entry transmitter. The system disarms when you unlock the doors with the keyless entry transmitter. The system does not disarm when you unlock the doors with the key.

Mode 3: The system arms when you lock the doors using a power door lock switch or the keyless entry transmitter. The system disarms when you unlock the left front, right front, or liftgate door with the key or the keyless entry transmitter.

Theft Deterrent Arm/Disarm Modes

Mode

Door Key Cylinder Lock Disarming

Power Door Lock Switch Arming

1

Enabled

Disabled

2

Disabled

Disabled

3

Enabled

Enabled

Changing the Feature Customization Modes

  1. Turn off the IP dimmer switch.
  2. Turn the ignition switch to the LOCK position.
  3. Remove the BCM PRGRM fuse.
  4. Turn the ignition switch to the ACC position. The BCM flashes the fasten belts indicator and sounds the chime 4 times, which indicates that BCM type 4 is installed on the vehicle. At this point, the BCM has entered the feature customization mode.
  5. In order to change the theft deterrent/shock sensor mode, turn the headlamp switch from OFF to PARK and back to OFF.
  6. The BCM flashes the fasten belts indicator and sounds the chime a number of times equivalent to the theft deterrent/shock sensor mode. A transition past mode 4 repeats the sequence starting with mode 1.

  7. Complete the following steps in order to change the theft deterrent arm/disarm mode:
  8. 6.1. Insert the key in the left front, right front, or liftgate door lock cylinder.
    6.2. Rotate the key from the center to the unlock position.
    6.3. Press the horn button on the remote keyless entry transmitter.
    6.4. Count the number of chimes that you hear. The number of chimes tells you which mode you have set.
    6.5. Press the horn button again in order to change the mode. Continue to press the button until you hear the number of chimes that indicates the mode that you want.
    6.6. Turn the key back to the center position and remove the key from the door key cylinder.

In order to exit and save the current feature customization modes use the following procedure:

  1. Turn the ignition switch to the LOCK position.
  2. Reinstall the BCM PRGRM fuse.

If you are unable to change locking modes Theft Deterrent System Feature Customization Inoperative