Originally Posted by STL
Once your air bags deploy don't you have to replace the control module because it is like a 1 time use thing?
CRASH SENSOR CHECKS
The air bag control module self-checks the crash sensors every time the engine is started, so unless the air bag warning light is on the sensors are assumed to be okay. If a fault is detected, the air bag warning light will come on and usually deactivate the air bag system. Using a scan tool, you can pull the trouble code from the system and refer to the appropriate diagnostic chart in a service manual to troubleshoot the problem. Air bag service information can also be found on the vehicle manufacturer's website (Click Here for a list of websites and access fees). Loss of circuit continuity anywhere in the air bag system, or loss of power to the air bag module are common causes of trouble codes.
Because crash sensors are sealed units, you cannot always determine their true condition by outward appearances. Any sensor that is obviously sustained physical damage as a result of a collision or other damage should be replaced. But what about ones that look okay? Most electromechanical crash sensors are designed to be electrically open in their rest condition. So one quick check you can perform is to check for continuity with an ohmmeter. If the sensor contacts are closed, it has not reset and should be replaced.
CAUTION! Do not attempt to check or replace any crash sensor unless the air bag module has first been deactivated (or deployed as a result of an accident). This can be done by unplugging the air bag connector at the base of the steering column and waiting at least 10 minutes or longer depending on the application (always refer to a service manual for the proper deactivation and removal procedure).