My brother passed away in an auto accident last year and my family is still working with insurance companies to work out some legal things with the lady that was involved. One big thing that has come up is the speed my brother was going when the accident happened. There's an entire story behind all this, but I'm going to go ahead and cut to the question. The airbags did not deploy in my brother's Blazer but there was enough force in the accident that they should have. We have heard that the "black box" that determines when the airbags deploy, and also keeps track of things like speed, recorded that the car was moving around 75-80 mph at the time of the accident, but since the airbags didn't deploy is there a chance that the black box could have been recording inaccurate information? Or was it most likely the airbags themselves that malfunctioned? Any responses are greatly appreciated.

 

I'm very sorry to hear about your brother. My prayers are with you and your family. My neighbor has worked in an auto shop as long as I've known him. When I got my 2000 I told him it's the first airbag system I've ever had. He explained that if the car is 10 years old or older. The airbags probably wont deploy. They use separate batteries since the main battery in the front can get damaged in the accident. Those separate batteries only last about 10 years. He fixes computers at night and has never given me wrong information. Recent news has proven shadiness in the airbag industry. I hope this is accurate. I couldn't find the batteries on my schematic. He may have said "batteries" as a layman's term for a specific power source. He tends to go over my head when he talks computers.

 

I believe what the news is talking about as a black box is just the computer

 

The news I was referring to is a recall on 34 million vehicles from 11 manufacturers for dangerous shrapnel blowing through the airbags. Takata paid over 1 million dollars in fines for refusing to release their findings. When they were finally ordered to produce them, the government ordered the largest recall in history.


The "black box" he's referring to stores vehicle info seconds before air bag deployment and at the moment they are deployed. Vehicle speed, whether or not the brakes were applied, and how much throttle a few seconds before and at the time of impact. Crash investigators use this information to determine what caused the accident.

 

Sorry nutz wasnt referring to your post, just what they perceive as black box

 

No worries guy. The term "black box" is actually the in flight recorder from airplanes. You're right about it being the computer. Like the freeze data on the computer. It records all the data at the time the code was triggered.

 

So it was most likely an airbag malfunction? And I wasn't sure the exact name for it, I just knew it behaved like the black box in airplanes and that it kept track of the data Nuts mentioned. Thanks a lot guys.

 

The module in question is the CDR, (Crash Data Retrieval) module. It is completely separate from the PCM, but it is part of the network and gathers data as necessary from other modules in the network. It continuously stores the previous 5 seconds of data, constantly updating itself. These modules have been installed in S&T body GM vehicles since 1998.

Typical stored data, depending on year, make, and model, is:


Vehicle speed (5 seconds before impact)


Engine speed (5 seconds before impact)


Brake status (5 seconds before impact)


Throttle position (5 seconds before impact)


State of driver’s seat belt switch (On/Off)


Passenger’s air bag enabled or disabled state (On/Off)


SIR Warning Lamp status (On/Off)


Time from vehicle impact to air bag deployment


Ignition cycle count at event time


Ignition cycle count at investigation


Time between near-deploy and deploy event (if within 5 seconds)


Hope this helps, prayers are with you.

 

Thanks Captain. And thanks everyone else. It's greatly appreciated.

 

What year Blazer? I'll see if I can dig up any more stuff that might help.