Air Bags

[Gordo]

How can I tell if the air bags in my truck are operational? My son had a recent incident wher I feel they should have gone off. They may have been used years ago and not replaced. Would like to know a safe way to determine their condition.

Thanks,

 

[The_Roadie]

The control module runs a continuous diagnostic on the wiring, sensors, and air bag firing mechanisms. If the *service SRS* light isn't on, the system is as good as it's possible to be checked.

 

[MAY03LT]

IIRC the airbag module does a bulb check and self test at every ignition on cycle. If the airbag light comes on when the key is turned on and goes out, it passed its self test. In some vehicles the light will blink a couple times before it goes out.

I don't know about the Avalanche but there has been many, many cases of airbags not going off in the TB/EVs when the owners felt that they should have.

edit: I type slow

 

[Jkust]

I've heard this from other people with various cars. Sometimes the angle of impact seemed not quite enough to set them off or at least that's what our common sense surmised. I always thought the old style/side of the seat mounted airbags in the Wife's first Rainier should have went off when she rolled it....but they didn't. The new side curtain/rollover airbags that stay inflated longer would have in her current Rainier. There was a story maybe 2 months back about counterfeit airbags that look normal from the outside but there's apparently no actual airbag inside or so showed the video.

 

[mrphoenix80]

Most GM cars the airbag light comes on at start up and flashes 7 times before going out. The only exceptions I can think of to this are the NUMMI cars (gm/toyota, vibe,prizm). In order for the bags to deploy it has to trip 2 sensors, first it has to see the decel sensor in the the SDM(airbag control module) and then the impact sensor or rollover sensor. Then it commands the bags to blow. When that command is given the SDM sets a hard code (B0??? deployment commanded) that can not be cleared by a scantool. The SDM needs to be replaced after deployment to clear this code, OR I have seen some people on ebay that take your module and reset it.

Could some one fool this system?? I suppose it is posible to install a junkyard SDM and fake bags that have the proper resistance. However if a deployment was commanded I would think it would still set the hard code and turn on the light.

We just had a 2011 Sierra in the shop with heavy front damage without airbag deployment. It hit so hard that it bent the rad support into a "V" but hit hit dead center between the front sensors. So I dont know if they where spared the impact required to command the bag to go off. From the damage I thought it should have. Estimate was like $10-12G's

 

[Gordo]

Thanks guys, seems mine are OK then as the computer shows no faults. Mine hit a rock face so hard, I had to buy another front end from a wreck and replace all the dented frame components. Peeled the skid plate clean off of it!

 

[Mark20]

An airbags deactivate module was discussed here about a year ago.

I've never really looked at the Voy's steering wheel air bag but my old Pontiac TranSport had a couple of slots in the bottom where you could see the bag folded up.