Airbag light on

Airbag light is on on my '96 5 lug. Came on last Saturday but didnt illuminate after sitting for an hour or 2, and was good all week. Today I am driving in town and it pops on again. Seemed to me that it came on after I hit a few small pot holes. But after it was on I drove @ 75 miles today, over both paved and rough gravel county roads and its still on. What are the first things I should check?

Horn and cruise still work....well, cruise works but wanders all over, if set for 65 it might randomly drop to 62 or go up to 68ish. But I dont think its the clock spring. Is there a sensor somewhere that might not be plugged it right or something? Crash sensor on the front end??

Thanks

 

The airbag (SRS) light can come on for a lot of reasons. It can be caused by a bad or dying battery, so check that first.
Also, if the battery is disconnected while the keys are in the ACC or ON position, it will generate a random SRS malfunction code that will need to be cleared

Anyway, what the SRS system does is check for electrical continuity in the system. If it finds out there's no continuity somewhere, the light will come on. Bad continuity is most of the time caused by a bad sensor:

Steering wheel clockspring (also known as spiral cable)
- when this one is going bad, it is usually accompanied by other symptoms such as horn not working, cruise control problems, turn signals coming on for no reason, and of course, the airbag light (one giveaway sign is when any of these problems happens especially when the steering wheel is being rotated)

crash sensors at the front of the truck (they sometimes corrode and go bad)

seat belt pretensionners

passenger airbag on/off switch

airbag computer or airbags themselves, but it is very rare to see these failing

to be sure of which one it can be, get the codes pulled out of the truck then post the result and I'll tell you what it means.

 

Battery is basically brand new, only 6 months old.

Ok, I dont think its the clockspring, I have noticed none of the other issues. Others I dont know, would have to do some research in them. Thats good list to start with though, thank you.

My truck only has a drivers side airbag as far as I know, so I dont think it has a switch on the passenger side. It should have a switch under the drivers side seat though right?

Ok, I will go to Oreillys tomorrow and see if they cant pull the airbag codes for me. I have a pocket OBD2 scanner but I have tried and I dont think it reads airbag codes.

 

If battery was changed while the keys were in the ACC or ON position, then it is why your light is on and you'll need to get the code cleared with a scan tool

Ah yes, true, 1996 trucks only have a driver airbag, so no passenger on/off switch for you. No switch under the seats, but the electrical connector under the driver's seat is for the seatbelt indicator and it is unrelated to the airbag

As to read the codes, you need a higher end scan tool, as standard ones can't read SRS codes. They only read check engine codes.
Some shops have these specialized scan tools and the dealership sure does too

 

Nope new battery was changed with the key off. I am sure the battery doesent have anything to do with it.

Yeah I know a place where they had a snap on scanner, local vo-tech school. But they are closed for the summer so that isnt an option. I am going to try jumpering the pins on the OBD2 and see if that tells me anything.

 

Just tried jumping the OBD2 pins, no luck. Maybe I was trying the wrong ones? Anyone know which are the correct 2 pins to jump?

 

no, shorting the OBD2 pins doesn't work. You can do his trick via the DIAGNOSTICS terminal in the engine bay. The pins to short are Tc and E1 (the diagram is on the inside of the cover when you flip it open).
Put the keys in the ACC or ON position and wait for 30 seconds then short the pins. The SRS light will blink in a pattern, telling you the code.
(example: blink - short pause - blink - blink - blink - blink - long pause - blink - short pause - blink - blink - blink - blink - long pause - and so on and on... This would indicate code 14 )

Make sure you short the right pins because it can damage the truck's computer

 

Ahh. Ok, maybe I will just find someone with a scanner that can get air bag codes, dont wanna mess up my ECU.

Yeah I have read codes off older OBD1 GM and other cars with airbag codes by shorting pins, so I know how to read them.

Ok well thanks for the help and will post back once I have a code.

 

Sounds to me (based on the fact that it comes on over bumps/rough roads) like you have a bad connection somewhere. The airbag systems in these older trucks are very simple, not much to them. First thing I would do is check the obvious things: connectors at the airbag module itself, connectors to the back of the steering wheel airbag, and any other connectors you can find. Make sure they are fully seated and no terminals are backed out or damaged. If everything looks good, you could have a failing module or wiring issue somewhere.

 

Ok, I will get my FSM and figure out where all the connections are to check. It seemed to come on when I hit some bumps but its still on and I have driven 200 miles like that. I pounded the some of the Oklahoma gravel county roads and the light still stayed on. Gonna get in touch with a guy I know at an auto shop and see if he doesent have a scanner that will retrieve airbag codes.

 

Alright, got in touch with a local mechanic. He printed off the All-Data sheet for retrieving airbag codes via DLC-1. Jumped the correct pins tonight and got codes 12 and 31. Any ideas? Havent looked up what they mean yet, going to do that now. If anyone has any input that would be great. The light went off for a couple seconds this morning and then came right back on. So idk what exactly is up. Hopefully the codes will shed a little light on it.

Thanks

 

code 31 indicates a malfunction in the airbag control module (computer)
code 12 indicates a short in D squib circuit (which consists of the airbag computer, clockspring [a.k.a. spiral cable] and steering wheel airbag)

Unfortunately, when the airbag light erratically comes on and pops a code 31, it usually means the airbag computer is faulty. But still, that doesn't mean you can't try to do a thing about it.
I've included the test procedures for codes 12 and 31
take care of code 12 first, as other codes can trigger a malfunction in the computer.

good luck

 

Ok thanks! Are airbag computers expensive or hard to find? It doesent look like its too hard to get to.

 

airbags computers are pricey, yes, but you can find them on ebay from junkyards for cheaper. The thing is that if the donor vehicle was involved in a crash, you will have to get it reset at the dealership

it's not too hard to get to the airbag computer. It's behind the centerpiece of the dash, right in front of the shifting lever and below the radio and cigarette lighter

 

Oh ok. I found a company online (myairbags) that will factory reset the module for like 50 bucks. But I wonder, would getting my module reset fix the problem? Or is it something else internally that is going bad?

 

when the computer goes bad, it is usually caused by a bad internal component, such as a bad capacitor. Resetting it won't fix the faulty component.

I guess you could find a shop that does car performance tuning, modding and chips and maybe they can do something for you? If not, you'll have to get another computer.
part # for a 96: 89170-35010

Though if you don't care about airbags, it's up to you to get the SRS system repaired or not. I mean, airbag issues won't prevent the truck from running, but it does cause a potential safety issue for you or anyone driving the truck because the airbags might not deploy in a crash

 

Ahh I see. Yeah I mean its only got a drivers side airbag. The older Yotas and cars didnt even have airbags so. I think '95ish was the first year with airbags for the trucks.

I am fine with driving it as is, but it would really be good to have them fixed. I wouldnt want to get into a crash where an airbag would have prevented a serious injury, but because I hadnt fixed it I get hurt bad kind of thing.

Thanks for the P/N, will do some looking around and see what I can find. I guess for code 12 I would have to ohm out all the D squip circuit components and see if any were faulty? I would hate to throw a module on it and have it not fix the problem...it just seems like code 12 means just about anything in the whole system could be bad haha.

 

Yeah, test components for code 12 before concluding your computer is definitely bad. As I said, another code can trigger a malfunction in the computer.

If it turns out it's the computer, they are generally considered not-repairable, but I'm sure there is a way to fix them. Maybe that company you talked about can fix it? Costs nothing to call and ask if they can do it. Just tell them that the computer itself has gone bad and it needs more than a reset

 

Hey guys, I’m dealing with the same exact problem in my ‘97. Did OP ever get it resolved?

 

I also have the preggo lady sitting on my gauge cluster...lmk if you find out whats going on?