GM Full-Size Trucks 1988-1998 Repair Information

General Information

Print

The Supplemental Inflatable Restraint (SIR) system offers protection in addition to that provided by the seat belt by deploying an air bag from the center of the steering wheel or dash panel. The air bag deploys when the vehicle is involved in a frontal crash of sufficient force up to 30° off the centerline of the vehicle. To further absorb the crash energy, there is also a knee bolster located beneath the instrument panel in the driver's area and the steering column is collapsible.

The system has an energy reserve, which can store a large enough electrical charge to deploy the air bag(s) for up to ten minutes after the battery has been disconnected or damaged. The system MUST be disabled before any service is performed on or around SIR components or SIR wiring.

SERVICE PRECAUTIONS



When performing service around the SIR system components or wiring, the SIR system MUST be disabled. Failure to do so could result in possible air bag deployment, personal injury or unneeded SIR system repairs.



When carrying a live inflator module, make sure that the bag and trim cover are pointed away from you. Never carry the inflator module by the wires or connector on the underside of the module. In case of accidental deployment, the bag will then deploy with minimal chance of injury.
 
When placing a live inflator module on a bench or other surface, always face the bag and trim cover up, away from the surface.
 

DISARMING THE SYSTEM



See Figure 1

With the AIR BAG fuse removed and the ignition switch ON, the AIR BAG warning lamp will be on. This is normal and does not indicate any system malfunction.

  1. Turn the steering wheel so that the vehicle's wheels are pointing straight ahead.
  2.  
  3. Turn the ignition switch to LOCK , remove the key, then disconnect the negative battery cable.
  4.  
  5. Remove the AIR BAG fuse from the fuse block.
  6.  
  7. Remove the steering column filler panel.
  8.  
  9. Disengage the Connector Position Assurance (CPA) and the yellow two way connector located at the base of the steering column.
  10.  
  11. Connect the negative battery cable.
  12.  



Click image to see an enlarged view

Fig. Fig. 1: Identification of the air bag system electrical connections

ARMING THE SYSTEM



  1. Disconnect the negative battery cable.
  2.  
  3. Turn the ignition switch to LOCK , then remove the key.
  4.  
  5. Engage the yellow SIR connector and CPA located at the base of the steering column.
  6.  
  7. Install the steering column filler panel.
  8.  
  9. Install the AIR BAG fuse to the fuse block.
  10.  
  11. Connect the negative battery cable.
  12.  
  13. Turn the ignition switch to RUN and make sure that the AIR BAG warning lamp flashes seven times and then shuts off. If the warning lamp does not shut off, make sure that the wiring is properly connected. If the light remains on, take the vehicle to a reputable repair facility for service.
  14.  

 
label.common.footer.alt.autozoneLogo