Expert: Douglas Gan - 10/13/2010

Question
I have a 2001 Audi A4. My airbag light went on after I was rear ended. No bag was deployed, now the mechanic says diagnostic shows all sensors ok. It gave 3 codes, one being that bag may be defective. Does the airbags need to fully be replaced? Is that costly? What if they are not replaced?

Answer
Hi Martha:

Sorry about your accident.  I hope you were not injured.

Regarding the airbag light.  On occasion, when a rear end collision occurs, it will trigger the control unit (located under the console.  Since it was a hit from the rear, the directional factor for an airbag deployment is wrong and the airbags will not deploy.  However, the control unit has now been compromised and is registering a fault, so most likely it will need to be replaced.
As far as the other codes, they are the determining factor in what component is at fault.  they could all lead to the control unit as well, and/or they may just need to be cleared.
An airbag specialist could help more than a regular shop or body shop as they may not be as familiar with SRS systems.
Finally, if you decide to drive with the airbag light on, the system will not deploy.  That light means the system is inactive and until it is out, you have no airbag protection.
I am enclosing a link to our company website to help you get a more thorough understanding of airbag systems.  
www.airbagsolutions.com

Good luck
Doug