GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Cadillac 🢒 1999 🢒 Eldorado 🢒 Body and Accessories 🢒 Data Link Communications 🢒 Inflatable Restraint Sensing and Diagnostic Module Replacement

Removal Procedure

    CAUTION: Be careful when you handle a sensing and diagnostic module (SDM). Do not strike or jolt the SDM. Before applying power to the SDM:

       • Remove any dirt, grease, etc. from the mounting surface
       • Position the SDM horizontally on the mounting surface
       • Point the arrow on the SDM toward the front of the vehicle
       • Tighten all of the SDM fasteners and SDM bracket fasteners to the specified torque value
    Failure to follow the correct procedure could cause air bag deployment, personal injury, or unnecessary SIR system repairs.

    Caution: If any water enters the vehicle's interior up to the level of the carpet or higher and soaks the carpet, the sensing and diagnostic module (SDM) and the SDM harness connector may need to be replaced. The SDM could be activated when powered, which could cause deployment of the air bag(s) and result in personal injury. Before attempting these procedures, the SIR system must be disabled. Refer to Disabling the SIR System.

    With the ignition OFF, inspect the SDM mounting area, including the carpet. If any significant soaking or evidence of significant soaking is detected, you must perform the following tasks:

    1. Remove all water.
    2. Repair the water damage.
    3. Replace the SDM harness connector.
    4. Replace the SDM.
    Failure to follow these tasks could result in possible air bag deployment, personal injury, or otherwise unneeded SIR system repairs.

  1. Disable the frontal SIR system. Refer to Disabling the SIR System .
  2. Remove the driver seat. Refer to Seat Replacement in Seats.
  3. Remove the right side sill plate.

    4. Object Number: 235763 Size: SH
  4. Lift up the carpet and insulation in order to access the inflatable restraint sensing and diagnostic module (SDM).
  5. Remove the CPA (4) from the SDM harness connector (3).

    6. Object Number: 235758 Size: SH
  6. Disconnect the SDM harness connector (3) from the SDM (1).

    7. Object Number: 235751 Size: SH
  7. Remove the SDM mounting fasteners (6).
  8. Remove the SDM (1) from the floor sheetmetal (2).

    9. Important: The following repair procedures should only be used in the event that the inflatable restraint sensing and diagnostic module (SDM) mounting studs and fasteners are damaged to the extent that the SDM can no longer be properly mounted.

  9. Utilize the following procedures if the SDM mounting fasteners or the SDM attachments are damaged:
    10. • If the SDM mounting bracket is broken loose from the floor sheetmetal at the weld, mig weld the bracket using the puddle weld method the spots that have broken loose. Always weld the bracket in the same spots as the original welds.

    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.

    • If an SDM attachment nut is missing or broken, slip a loose nut (PN 11515741) under the SDM bracket. While you hold the nut in place, install the bolt PN 11515925.

    Tighten
    Tighten the fasteners to 9 N·m (80 lb in).

    • If the ground wire nut is missing, drill an 8 mm (0.315 in) hole in the bracket to 12 mm (0.472 in). Tack weld a loose weld nut PN 20530601 to the bracket in place of the missing nut. Fasten the ground wire using the original bolt PN 3578880.

    Tighten
    Tighten the fasteners to 6 N·m (54 lb in).

    • If the SDM attachment nut or ground nut is stripped, drill a 6.5 mm (0.256 in) hole through the weld nut. Use a new 7 mm bolt, PN 10267482, in order to fasten the SDM or the ground wire.

    Tighten
    Tighten the fasteners to 16 N·m (12 lb ft).

    • If the SDM attachment bolt or ground bolt is broken, use a tap, bolt remover or drill in order to remove the broken bolt. Drill a 6.5 mm (0.256 in) hole through the weld nut. Use a new 7 mm bolt, PN 10267482, in order to fasten the SDM or the ground wire.

    Tighten
    Tighten the fasteners to 16 N·m (12 lb ft).

Installation Procedure

    Object Number: 235751 Size: SH
  1. Install the SDM (1) to the floor sheetmetal (2).

    2. 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.

  2. Install the SDM mounting fasteners (6).

    3. Tighten
    Tighten fasteners to 9 N·m (80 lb in).


    Object Number: 235758 Size: SH
  3. Install the SDM harness connector (3) to the SDM (1).

    4. Object Number: 235763 Size: SH
  4. Install the CPA (4) to the SDM (3) harness connector.
  5. Install the right side sill plate.
  6. Install the driver seat. Refer to Seat Replacement in Seats.

    7. 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.

  7. Enable the frontal SIR system. Refer to Enabling the SIR System .