SIR Disabling and Enabling

Warning

When performing service on or near the SIR components or the SIR wiring, the SIR system must be disabled. Failure to observe the correct procedure could cause deployment of the SIR components. Serious injury can occur. Failure to observe the correct procedure could also result in unnecessary SIR system repairs. SIR component location affects how a vehicle should be serviced. There are parts of the SIR system installed in various locations around a vehicle. For the location of the SIR components, refer to Master Electrical Component List. There are several reasons for disabling the SIR system, such as repairs to the SIR system or servicing a component near or attached to an SIR component. There are several ways to disable the SIR system depending on what type of service is being performed. The following information covers the proper procedures for disabling/enabling the SIR system. If the vehicle was involved in a collision, refer to Repairs and Inspections Required After a Collision

Condition	Action
Performing diagnosis or repairs on or near SIR components. Examples but not limited to the following: Floor/Center console, steering wheel, dash components, seats, floor shifters, HVAC case, doors, door strikers, carpet replacement, etc Refer to: Master Electrical Component List	Disconnect the negative battery cable*
Performing electrical diagnosis on components other than the SIR system	Remove the SIR/Airbag fuse(s) when indicated by the diagnostic procedure to disable the SIR system
Vehicle was involved in an accident with an airbag deployment	Disconnect the negative battery cable*
Performing SIR diagnostics	Follow the appropriate SIR service manual diagnostic procedure(s)*
Removing or replacing an SIR component or a component attached to an SIR component	Disconnect the negative battery cable*
The vehicle is suspected of having shorted electrical wires	Disconnect the negative battery cable*
* DTCs will be lost when the negative battery cable is disconnected.

SIR Service Precautions

Warning

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.

Warning

When performing service on or near the SIR components or the SIR wiring, the SIR system must be disabled. Failure to observe the correct procedure could cause deployment of the SIR components. Serious injury can occur. Failure to observe the correct procedure could also result in unnecessary SIR system repairs. The Restraints Control Module (RCM) maintains a reserved energy supply. The reserved energy supply provides deployment power for the airbags if the Restraints Control Module loses battery power during a collision. Deployment power is available for as much as 2 minutes after disconnecting the vehicle power. Wait 2 minutes before working on the system after disabling the SIR system to prevent deployment of the airbags from the reserved energy supply. General Service Instructions The following are general service instructions which must be followed in order to properly repair the vehicle and return it to its original integrity: Do not expose airbags to temperatures above 85 °C (185 °F). Verify the correct replacement part number. Do not substitute a component from a different vehicle. Use only original GM replacement parts available from your authorized GM dealer. Do not use salvaged parts for repairs to the SIR system. Discard any of the following components if it has been dropped from a height of 80 cm (31.5 in) or greater: Restraints Control Module Restraint Occupant Classifcation System Airbag Driver steering wheel airbag coil Seat belt pretensioner Impact sensor Disabling Procedure – Airbag Fuse

1. Turn the steering wheel so that the vehicles wheels are pointing straight ahead.
2. Vehicle OFF.

Warning

The SDM may have more than one fused power input. To ensure there is no unwanted SIR deployment, personal injury, or unnecessary SIR system repairs, remove all fuses supplying power to the SDM. With all SDM fuses removed and the ignition switch in the ON position, the AIR BAG warning indicator illuminates. This is normal operation, and does not indicate a SIR system malfunction.

3. Locate and remove the fuse(s) supplying power to the Restraints Control Module. Refer to SIR Schematics.
4. Wait 2 minutes before working on the system. Enabling Procedure – Airbag Fuse
5. Vehicle OFF.
6. Install the fuse(s) supplying power to the Restraints Control Module. Refer to SIR Schematics
7. Vehicle in Service Mode. The Airbag indicator will cycle ON then cycle OFF.
8. Perform the Diagnostic System Check – Vehicle if the Airbag warning indicator does not operate as described. Refer to Diagnostic System Check - Vehicle. Disabling Procedure – Negative Battery Cable
9. Turn the steering wheel so that the vehicles wheels are pointing straight ahead.
10. Vehicle OFF.
11. Disconnect the negative battery cable from the battery. Refer to Battery Negative Cable Disconnection and Connection.
12. Wait 2 minutes before working on system. Enabling Procedure – Negative Battery Cable
13. Vehicle OFF.
14. Connect the negative battery cable to the battery. Refer to Battery Negative Cable Disconnection and Connection.
15. Vehicle in Service Mode. The Airbag indicator will cycle ON then cycle OFF.
16. Perform the Diagnostic System Check – Vehicle if the Airbag warning indicator does not operate as described. Refer to Diagnostic System Check - Vehicle.