Changing front end need to know where the air bag deployment sensors are and what I need to do so they won't go off?

This sensor mounts on the front of the vehicle, behind the front bumper, on the frame rail.

2006-2008 Pontiac Grand Prix Front Airbag Air Bag Sensor ...

https://www.google.com/search?q=05+Pontiac+GP+air+bag+sensors+location

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There are more than one sensor used to deploy the air bag none mounted at the air bag. the switch is a sealed tube with a ball inside ,a magnet to hold the ball at one end and a pair of contacts at the other end. on impact the ball moves forward and closes the contacts. Make sure the battery is removed before playing with air bag switches . It is quite costly if the bag is deployed.

Front air bags are not designed to deploy in side impact, rear impact or rollover crashes.There are several reasons why your air bag may not have deployed during a crash. The first reason is that perhaps your crash is not the type of accident where air bag deployment would be helpful. For frontal air bags, this includes many, but not all, side impacts, rear impacts and rollovers. This category also includes minor accidents in which the driver and front passenger (if there was one) did not suffer any significant injuries requiring medical treatment. Many people do not realize there are a lot of side air bags that do not deploy during a rollover accident, even when the vehicle rolls onto its side. That is because those side air bags do not include an appropriate crash sensor that can detect rollover crashes.

The crash sensors are located inside the computer the accelarometer would of been replaced if the computer was replaced. Or the air bag control modual. The clock spring would need to be replaced but the front magnetic sensors should be fine, they don't normally wear out. they can be damaged but the air bag warning light would flash if it was bad. And the air bag would still not go off unless the other condtions are met to make the bag deploy. The air control modual would have been replaced if it was done by a shop that is part of the service when the bags deploy. The crash sensors are a magnet with a steel ball and when the right speed is reached and the ball is let go from the metal o ring that it sits in it will deploy the first trigger the next trigger would be the acelorometer in the air control module and the impact would have to be strong enought to knock that ball loose as well to trigger the air bag.

http://www.nhtsa.dot.gov/cars/problems/ is the website I checked for your car and found no reference to this issue. There are reports of airbag deployments with no collisions, although they are rare. The computer in your car is capable of displaying the deployment, and may show which sensor in the front if any caused it to deploy (collision first/deployment second) or if no sensor signal (deployment first / collision second) is logged. Whatever the outcome, you will need a specialist in data extraction to achieve this.

the air bags are very costlly, like around 2,000-4,000 eachwith out labor. the sensors are a few hundred also. when you replace the air bags you should replace all of the sensors. very expensive. for that kind of money you could almost get a new van. using junk yard air bags i don't suggest. to risky.

You triggered the impact sensor.(usually on or near the front bumper) It will need to be re-set or replaced, and obviously, you need to replace airbag.

you need to buy new air bags and a new computer for the air bags you will also need to replace the clock spring in the steering wheel, I do not suggest you do this without knowing anything about the air bag system as it can kill you. This one is for a professional, and the older cars have added items that need to be checked like accelerometers and crash sensors on the front of the radiator core support and on each fender, any one of these items could deploy the air bag if defective. and the old ones deploy at 180 miles per hour.

front air bags only go off when hit in front endthey go off at 15 miles a hour

I suspect it's more the force of the impact that sets them off... there are sensors on the front end.