GM Service Manual Online
For 1990-2009 cars only

Removal Procedure

    Caution: When performing service on or around the SIR components or the SIR wiring, follow the procedures listed below in order to temporarily disable the SIR system. Failure to follow the procedures could result in the following:

       • Air bag deployment
       • Personal injury
       • Otherwise unneeded SIR system repairs

  1. Disable the SIR system. Refer to SIR Disabling and Enabling .
  2. Remove the Inflatable Restraint Steering Wheel module. Refer to Inflatable Restraint Steering Wheel Module Replacement .

  3. Object Number: 399638  Size: SH
  4. Remove the horn plunger from the steering column by pressing inward to the stop and by rotating the plunger 90 degrees.

  5. Object Number: 776565  Size: SH
  6. Disconnect the screws (1, 4) from the steering wheel (3).
  7. Remove the horn switch (2) from the steering wheel (3).

Installation Procedure


    Object Number: 776565  Size: SH
  1. Install the horn switch (2) to the steering wheel (3).
  2. Notice: Refer to Fastener Notice in the Preface section.

  3. Connect the screws (1, 4) that secure the contact plate to the steering wheel (3) .
  4. Tighten
    Tighten the screws to 5.5 N·m (49 lb in).


    Object Number: 399638  Size: SH
  5. Install the horn plunger to the steering column.
  6. Install the inflator module. Refer to Inflatable Restraint Steering Wheel Module Replacement .
  7. Enable the SIR system. Refer to SIR Disabling and Enabling .