GM Service Manual Online
For 1990-2009 cars only

The content theft deterrent system operates separately from the immobilizer system. The immobilizer system is standard on this vehicle. The content theft deterrent system design provides a warning in the event of forced entry through the doors or the rear compartment lid. The alarm system trips in the event of forced entry. The horn sounds intermittently and the exterior lamps flash in unison under the alarm system. The alarm remains active as long as any door remains open. The alarm continues to sound for 3 minutes once all the doors close. Once the 3 minute time expires the horn and the lights deactivate and the system returns to an armed state. The content theft deterrent system does not affect the engine starting or the engine operation.

Arming the Content Theft Deterrent System

Perform the following steps in order to enable the normal arming procedure when exiting the vehicle:

  1. Close all the windows.
  2. Place the shift lever in the PARK position.
  3. Turn the ignition switch to the LOCK position.
  4. Remove the ignition key.
  5. Open any door.
  6. Use the power door lock switch or use the transmitter LOCK button to lock the doors.
  7. Close the doors in order to initiate the following conditions:
  8. 7.1. The SECURITY lamp illuminates solid on the dash for 30 seconds.
    7.2. The system is fully armed once the SECURITY lamp goes out.

Locking without Arming

Manually lock the doors manually with the inside lock knobs or with the front door lock key, then close the doors in order to lock the vehicle without arming the system.

Alarm Activation

The armed system activates by sounding the horn and intermittently cycling the lights in unison with the opening of the trunk or any door. The BCM senses door opening through the door jamb switch. The BCM senses trunk opening through the trunk jamb switch. This alarm can be armed with the windows either open or closed since the system activation is dependent on door or trunk opening. The alarm disarms only when a door opens with the front door lock key or with the transmitter.

The doors and trunk can still open without alarm activation anything during the 30 second arming period. The security indicator lamp in the instrument panel flashes intermittently in order to remind the driver to relock the doors and arm the system. The system begins the arming process once the doors are locked with the use of the power door lock switch or the transmitter and all the doors shut. The SECURITY lamp illuminates solid for 30 seconds once the last door closes. The system is fully armed once the SECURITY lamp goes out.

Disarming the System


Object Number: 160872  Size: SH

The system disarms during the 30 second arming sequence under any of the following actions:

    • The opening of any door
    • Unlocking the doors with the power door lock switch
    • Unlocking the doors with the transmitter
    • Unlocking the doors with the front door lock key

Unlock the driver side door with the key, or depress the UNLOCK button (1) on the transmitter in order to disarm the system after the system is fully armed or possibly tripped.

Theft Deterrent Switch

The front driver door is equipped with a theft deterrent switch. The theft deterrent switch attaches to the lock cylinder. The theft deterrent switch activates by movement of the lock cylinder. The theft deterrent switch activates under the following conditions:

    • Rotation of the lock cylinder caused by forced entry
    • The in-and-out movement caused by forced entry

Additionally, use the theft deterrent switch in order to disarm the system. The switch grounds the disarm input to the BCM when the lock cylinder turns in order to unlock the door. The switch is serviceable. Remove the switch from the door latch in order to service the switch.

Mechanical failure and/or corrosion on the switch may cause the system to self-activate intermittently. Inspect the lock cylinder for looseness if this happens. Any movement of the lock cylinder with this switch can cause the switch to activate the alarm. One possible cause for this problem may be a lock cylinder retainer that is not firmly installed to the lock cylinder. Reinstall the lock cylinder retainer or replace the lock cylinder retainer with a new retainer in order to correct this problem.

Door Jamb Switches

The content theft deterrent system uses the door jamb switches and the trunk jamb switch in order to activate the alarm. The BCM uses these switches in order to monitor door and trunk status. The BCM appropriately activates the following components if tripped or armed:

    • The parking lamps
    • The headlamps
    • The horn

Horn, Parking Lamp and Headlamp Relays

The relays provide power for the following components when the alarm system activates:

    • The horn
    • The exterior lamps
    • The headlamps

The BCM solely controls and actuates the relays with the exception that the horn relay can also activate through the steering wheel contacts.

Security Lamp


Object Number: 160874  Size: SH

The SECURITY lamp (1) circuit is an indicator lamp output. The lamp illuminates under various operating conditions. For example, the lamp illuminates during the 5 second bulb test at key on. The SECURITY indicator lamp illuminates solid for 30 seconds. The system is fully armed once the SECURITY indicator lamp goes out.