SIR component location affects how a vehicle should be serviced. There are parts of the SIR system installed in various locations around a vehicle. To find the location of the SIR components refer to SIR Identification Views.
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.
Condition | Action |
If the vehicle was involved in an accident with an air bag deployment. | Disconnect the negative battery cable(s) *. Refer to Repairs and Inspections Required After a Collision. |
When performing SIR diagnostics. | Follow the appropriate SIR service manual diagnostic procedure(s) * |
When moving, removing or replacing an SIR component or a component attached to an SIR component. (Anytime you remove fasteners.) | Disconnect the negative battery cable(s) * |
If the vehicle is suspected of having shorted electrical wires. | Disconnect the negative battery cable(s) * |
When 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 |
* DTCs will be lost when the negative battery cable is disconnected. |
SIR Service Precautions
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 inflatable restraint sensing and diagnostic module (SDM) maintains a reserved energy supply. The reserved energy supply provides deployment power for the air bags if the SDM loses battery power during a collision. Deployment power is available for as much as 1 minute after disconnecting the vehicle power. Waiting 1 minute before working on the system after disabling the SIR system prevents deployment of the air bags 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:
Discard any of the following components if it has been dropped from a height of 91 cm (3 feet) or greater:
Disabling Procedure - Air Bag Fuse
Note: 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.
Enabling Procedure - Air Bag Fuse
Disabling Procedure - Negative Battery Cable
Enabling Procedure - Negative Battery Cable
Special Tools and Equipment
Malfunction Indicator Lamp
A computer system called OBD II (On-Board Diagnostics-Second Generation) monitors
the operation of the vehicle to ensure emissions are at acceptable levels, helping
to maintain a clean environment.
The malfunction indicator lamp comes on when the vehicle is placed in ON/RUN
for key access or ...
Installation Procedure
Remove all mounds or loose pieces of urethane adhesive from the
pinch-weld area.
Inspect for any of the following problems in order to help prevent
future breakage of the window:
High weld
Solder spots
Hardened sealer
Any other obstruction or irregularity in the pinch-weld fla ...
Traction Control System (TCS)
The vehicle has a Traction Control System (TCS) that limits wheel spin.
On a front-wheel-drive vehicle, the system operates if it senses that one or
both of the front wheels are spinning or beginning to lose traction. When this happens,
the system brakes the spinning wheel(s), and/or reduces en ...