Performing work on a vehicle equipped with an airbag safety restraint system can be dangerous, as an accidental airbag deployment can cost the shop a hefty sum if an airbag needs to be replaced due to unsafe service actions. There is also the very real risk of serious personal injury to the technician. Whenever diagnosing or servicing an airbag system, or working on the steering column area or SRS activation sensors, proper safety precautions must be followed to prevent accidental discharge.
Airbag deactivation procedures differ among makes/models/years, so always refer to the appropriate service manual for the correct method. NEVER assume that any specific deactivation procedure is correct for all airbag-equipped vehicles.
Listed here are a few examples of recommended procedures. Bear in mind that the procedures listed here are provided merely as examples of procedures. ALWAYS refer to the applicable factory service guidelines for the correct procedure for any given vehicle!
Inspecting an airbag module using a tester can deploy the airbag module, which may cause serious injury. DO NOT use a tester to inspect an airbag module. Always use the on-board diagnostic function to diagnose the module for malfunctions.
Before removing the airbag module or disconnecting the air bag module connector, always turn the ignition switch to the LOCK position, disconnect the negative battery cable (and isolate the cable end using an isolator such as electrical tape), then wait for one minute or more to allow the backup power supply of the SAS control module to deplete its stored power.
2012 Jeep Grand Cherokee
To avoid serious or fatal injury on vehicles equipped with air bags, disable the SRS (supplemental restraint system) before attempting any steering wheel, steering column, airbag, seat belt tensioner, impact sensor or instrument panel component diagnosis or service.
Disconnect and isolate the battery negative (ground) cable, then wait at least two minutes for the system capacitor to discharge before performing further diagnosis or service. This is the only sure way to disable the SRS. Failure to take the proper precautions could result in accidental airbag deployment.
In addition to a diagnostic scan tool that contains the latest version of the proper diagnostic software, certain diagnostic procedures for the SRS may require the use of the SRS Load Tool special tool along with the appropriate Load Tool jumpers and adapters.
2012 Audi A6 Sedan
1. Never test airbag units with a test light, volt meter or ohm meter.
2. The pyrotechnic components may be checked only when they are installed and with a Volkswagen-approved vehicle diagnosis, testing and information system.
3. When working on pyrotechnic components and on the airbag control module J234, the battery ground cable must be disconnected, with the ignition switched ON. Then cover the negative terminal.
4. Wait for 10 seconds after disconnecting the battery.
5. The ignition must be switched ON when connecting the battery. Nobody should be inside the vehicle while doing this. The exception: vehicles with a battery inside the passenger compartment. Stay away from the airbags and the safety belts.
6. If after reconnecting the battery, the ignition does not turn on (indicator lamp in the instrument cluster does not illuminate), keep your head and arms as far away from the steering wheel and the installed knee airbag as possible, so that they are not near the airbags and the safety bets during the first attempt to start the ignition.
7. Before handling pyrotechnic components of the restraint system, for example, before disconnecting the electrical harness connector, the technician must discharge static electricity. Touching grounded metal parts, for example, touching the door striker, will discharge the static electricity.
General airbag handling
When carrying a live (un-deployed) airbag module, point the deployment surface AWAY from your body. When storing the module on a bench or other surface, be sure to place the module with the deployment surface facing upwards, not facing the bench or floor surface. If the module accidentally deploys, serious injury can result if the deployment surface faces the body. If stored face-down on a surface and deployment occurs, the module will fly upwards with significant force.
Treat every airbag module as you would a loaded or unloaded firearm. Even if you have removed battery power and have provided the recommended power-down discharge time for the module, do not assume that it is “unloaded.” Always handle carefully and always keep the deployment surface aimed in a safe direction.
Whenever servicing an SRS module, only the trained technician who is performing the service should be inside the vehicle.
Whenever performing service inside the vehicle that contains airbag modules, always wear eye protection, a long-sleeve shirt or jacket, and protective work gloves. Ear protection is also highly recommended. Protection against potential burns, hearing damage and vision damage is critical. Minimize the extent of exposed skin on the body.
Carefully inspect all seat belts, buckles, mounting hardware, retractors, tether straps and anchors for proper installation, operation or damage. Replace any seat belt that is cut, frayed or torn. Straighten-out any belt that is twisted. Never attempt to repair a seat belt or child restraint component. If damaged, always replace any system components with new OEM parts.
If dealing with an ignited restraint system pyrotechnic component, wash your hands after touching/handling.
Pyrotechnic components that have fallen onto a hard surface or show signs of damage must not be installed to the vehicle.
New pyrotechnic components should be installed immediately upon removal of shipping packages or returned to the shipping package until you are ready for installation.
The cost of replacing airbags can vary depending on the number of bags, the make and model and if related items require replacement, such as the SRS ECU, sensors, steering wheel, windshield, etc. Costs to the customer or insurance agency including parts and labor can easily range from $1,000 to well over $6,000, which is a factor in determining if the vehicle is worth repairing or is considered a total loss. ■
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