GM Service Manual Online
For 1990-2009 cars only

Removal Procedure

    Caution: Refer to SIR Caution in the Preface section.

    Caution: Do not strike or jolt the inflatable restraint sensing and diagnostic module (SDM). Before applying power to the SDM, make sure that it is securely fastened with the arrow facing toward the front of the vehicle. Failure to observe the correct installation procedure could cause SIR deployment, personal injury, or unnecessary SIR system repairs.

    Caution: If the vehicle interior is exposed to moisture and becomes soaked up to the level of the sensing and diagnostic module (SDM), the SDM and SDM harness connector must be replaced. The SDM could be activated when powered, which could cause airbag deployment and result in personal injury.

  1. Disable the SIR system. Refer to SIR Disabling and Enabling .
  2. Remove the accessory trim plate. Refer to Instrument Panel Accessory Trim Plate Replacement in Instrument Panel, Gages and Console.

  3. Object Number: 391030  Size: SH
  4. Remove the heater and A/C control head.
  5. Remove the connector position assurance (CPA) from the SDM harness connector.

  6. Object Number: 391032  Size: SH
  7. Disconnect the SDM harness connector.

  8. Object Number: 391034  Size: SH
  9. Remove the SDM (3) mounting fasteners (2).
  10. Remove the SDM from the I/P center support system (1).

Installation Procedure

  1. Remove any dirt, grease, or other impurities from the mounting surface.

  2. Object Number: 391034  Size: SH
  3. Install the SDM (3) horizontally to the I/P center support system (1).
  4. Point the arrow on the SDM toward the front of the vehicle.
  5. Notice: Use the correct fastener in the correct location. Replacement fasteners must be the correct part number for that application. Fasteners requiring replacement or fasteners requiring the use of thread locking compound or sealant are identified in the service procedure. Do not use paints, lubricants, or corrosion inhibitors on fasteners or fastener joint surfaces unless specified. These coatings affect fastener torque and joint clamping force and may damage the fastener. Use the correct tightening sequence and specifications when installing fasteners in order to avoid damage to parts and systems.

  6. Install the SDM mounting fasteners (2).
  7. Tighten
    Tighten the fasteners to 10 N·m (89 lb in).


    Object Number: 391032  Size: SH
  8. Install the SDM harness connector to the SDM.

  9. Object Number: 391030  Size: SH
  10. Install the CPA to the SDM harness connector.
  11. Install the heater and A/C control head.
  12. Install the accessory trim plate. Refer to Instrument Panel Accessory Trim Plate Replacement in Instrument Panel, Gages and Console.
  13. Important: The AIR BAG indicator may remain ON after the SDM has been replaced. DTC B1001 may set requiring the SDM part number to be set in multiple modules. If the indicator remains ON after enabling the SIR system, perform the diagnostic system check and follow the steps thoroughly to ensure that the SDM is set properly.

  14. Enable the SIR system. Refer to SIR Disabling and Enabling .