GM Service Manual Online
For 1990-2009 cars only

Alarm System Inoperative Genuine Accessory

Diagnostic Fault Information

Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.

Circuit/System Description

The alarm system integrates into the existing vehicle wiring system. The alarm system is designed as a theft deterrent and incorporates all doors, trunk lid and hood status sensing, ultrasonic movement sensing and vehicle inclination sensing. When the alarm system is in an armed state and any security violation is detected, the alarm module will sound the siren. The alarm system may be unable to initialize due to the following :

    • Power supply or ground has open/high resistance.
    • Tilt sensor incorrectly connected to the alarm module.

Reference Information

Schematic Reference

Theft Deterrent System Schematics

Connector End View Reference

Component Connector End Views

Electrical Information Reference

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

Circuit/System Testing

Power Supply or Ground Has Open/High Resistance

  1. Ignition OFF, disconnect the alarm module harness connector.
  2. Verify that a test lamp illuminates between the B+ circuit terminal 1 and ground.
  3. If the test lamp does not illuminate, test the B+ circuit for a short to ground or an open/high resistance.
  4. Test for less than 1.0 Ohm of resistance between the ground circuit terminal 6 and ground.
  5. If greater than the specified range, test the ground circuit for an open/high resistance.
  6. Ensure that the tilt sensor mounting bracket bolts are tightened to 6 Nm.
  7. Disconnect the harness connecter from the tilt sensor.
  8. Ensure that the harness connecter terminal 2 is vacant.
  9. Test for less than 1.0 Ohm of resistance between the tilt sensor harness connector terminal 4 and ground.
  10. If greater than the specified range, test the ground circuit for an open/high resistance.
  11. Connect the alarm module harness connector. From inside the vehicle, enable the alarm system with the remote transmitter key. Test for 9-16  volts between the tilt sensor 12-volt reference circuit terminal 1 and ground.
  12. If less than the specified range, test the 12-volt reference circuit for a short to ground or an open/high resistance.
    If greater than the specified range, test the 12-volt reference circuit for a short to voltage.
  13. Disconnect the alarm module harness connector and test for less than 1.0 Ohm of resistance between the alarm module harness connector terminal 4 and the tilt sensor harness connector terminal 3
  14. If greater than the specified range, test the circuit for an open/high resistance.
  15. Test for infinite resistance between the alarm module harness connector terminal 4 and ground.
  16. If not the specified value, replace the alarm module harness.
  17. Replace the tilt sensor and test the alarm operation.
  18. If alarm system is still inoperative, replace the alarm module.

Repair Instructions

For component removal and installation refer to the accessory fitting instructions.