Post-Collision Repairs

While servicing an air bag equipped vehicle that has been involved in an accident, check the sensors and wiring for damage.

Sensors

WARNING: VEHICLE SENSOR ORIENTATION IS CRITICAL FOR PROPER SYSTEM OPERATION. IF A VEHICLE EQUIPPED WITH AN AIR BAG SYSTEM HAS BEEN INVOLVED IN A CRASH WHERE THE FENDERS OR GRILLE AREA HAVE BEEN DAMAGED, INSPECT THE SENSOR MOUNTING BRACKETS FOR DEFORMATION. IF DAMAGED, THE SENSOR SHOULD BE REPLACED WHETHER OR NOT THE AIR BAG IS DEPLOYED. IN ADDITION, ENSURE THAT THE BODY STRUCTURE IN THE AREA OF THE SENSOR MOUNTING IS RESTORED TO ITS ORIGINAL CONDITION.

NOTE: Undamaged sensors will reset automatically after an accident and can be reused.

Damaged Wiring

CAUTION: Before attempting diagnostic prove out, check for wiring shorts that could cause the air bag diagnostic monitor thermal fuse to blow (open), causing unnecessary replacement.

Inspect the sensor wiring and the wiring harness for any damage that may have occurred as a result of the accident. Replace as required any damaged:
- wiring.
- terminals.
- insulation.
- connectors.

If splices are required in adjacent wiring, the splices should be staggered 50 mm (2 inches) apart from each other. Service splices as follows:
- Use a waterproof butt-splice connector on any exposed wiring.
- A heat shrink nylon splice prevents water, salt, condensation and heat from affecting the wiring service.





The inner wall of the splice connector is lined with an adhesive that melts when heated with a heat gun and flows under pressure from the tubing, sealing the splice. The connectors can be crimped with a standard insulated connector crimping tool. The splices are color coded for gauge identification and are transparent to allow inspection of the finished splice.

Steering Column
If the accident involved an air bag deployment, the steering column may have been loaded sufficiently to deform the steering column mounting brackets or damage the column wiring. An inspection should be made of the column structure and clockspring wiring to ensure that any damaged components are replaced.

Supplemental Air Bag Restraint System (SRS)

CAUTION: Before attempting diagnostic prove out, check all sensors and wiring for damage or shorts that could cause the air bag diagnostic monitor thermal fuse to blow (open), causing unnecessary replacement.

After all service is completed, verify the air bag lamp operation as follows:
- Turn the ignition switch to the ON position.
- Count the air bag lamp flashes only after the code (series of flashes) has cycled twice.
- If the air bag lamp illuminates continuously for four to eight seconds and then goes out, the SRS is functioning properly and all faults have been serviced. If the air bag lamp does not illuminate, illuminate continuously for four to eight seconds then go out, or remains continuously illuminated, there is a malfunction in the SRS.