GM Service Manual Online
For 1990-2009 cars only

Diagnostic Instructions

    • Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
    • Review Strategy Based Diagnosis for an overview of the diagnostic approach.
    •  Diagnostic Procedure Instructions provides an overview of each diagnostic category.

Circuit/System Description

The Vehicle Intrusion Sensor is a component of the Content Theft Deterrent system which monitors the vehicle interior and provides an alarm signal to the body control module (BCM) in the event of an unauthorized entry into the vehicles interior. The Intrusion sensor ground is controlled through a switched ground output from the BCM. By providing ground from the BCM the Intrusion sensor is powered-up and activated.

Reference Information

Schematic Reference

Theft Deterrent System Schematics

Connector End View Reference

Theft Deterrent System Connector End Views

Description and Operation

Content Theft Deterrent (CTD) Description and Operation

Electrical Information Reference

    •  Circuit Testing
    •  Connector Repairs
    •  Testing for Intermittent Conditions and Poor Connections
    •  Wiring Repairs

Scan Tool Reference

Scan Tool Data List

Circuit/System Testing

  1. Ignition OFF, disconnect the harness connector at the intrusion sensor.
  2. Ignition OFF, test for less than 1.0 ohm of resistance between the low reference circuit terminal C and ground.
  3. If greater than the specified range, test the low reference circuit for an open/high resistance.
  4. Ignition ON, verify a test lamp illuminates between the B+ circuit terminal A and ground.
  5. If the test lamp does not illuminate, test the B+ circuit for a short to ground or an open/high resistance.
  6. Test for B+ between the Intrusion Sensor Alarm On Signal circuit terminal B and ground.
  7. If not the specified value, test the signal circuit terminal 3 for a short to ground or an open/high resistance. If the circuit tests normal, replace the BCM.
  8. If all circuits test normal, replace the intrusion sensor.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

Refer to Control Module References for BCM and XBCM replacement, setup, and programming.