Airbag error 12 & fuse 4 instantly popping

tachicardia · Aug 4, 2016

So I just bought a 96 mystic cobra that was sitting in storage for 10+ years. One of the kinks I'm trying to work out is the Airbag error light the car has. It's giving me an error code 12. I narrowed down the issue to fuse 4 (under the dash) being blown. With the car off and no keys in the ignition I replace the fuse and it was instantly blown. I pulled that fuse and replaced with another new 10amp fuse, it didn't even make its way into the slot and was blown. I could even hear the contacts sparking as I put the fuse in.

So, clearly the 12 error code is that power isn't reaching the module because of the fuse - but if I can't replace the fuse I can't further trouble shoot the issue. Has anyone seen this before or have any ideas on how to start to figure this out? Would a loose ground cause this situation? I would have thought the fuse would pop with the car on or running, not be burnt out instantly with the car off. It sounds like somehow that line is getting overloaded with power with the car off.

FYI the car has 25XXX miles and is otherwise in great looking/running shape.

Thanks!
Eric

ttocs · Aug 4, 2016

first - do NOT replace a blown fuse with a larger fuse ever again. Hopefully you didn't do any further damage. Has the car been in any accidents? Was the heater core replaced recently or the steering wheel out for any reason?

tachicardia · Aug 4, 2016

10amp was the original size, a bigger fuse was never put in :thumbsup:

No accidents, steering wheel wasn't removed and heater core is original. Cruise control and horn both work so it's likely not the clock spring (as far as I can tell from what I've read).

07GtS197 · Aug 4, 2016

Have you tried resetting the airbag computer by jumping the gray connector under the glove box? It could be nothing or it could be something like a bad ground or the airbag computer is bad.

Mustanger · Aug 4, 2016

if the fuse blows instantly that indicates a hot wire to ground short...like a skinned wire touching metal or some other failure like that. get a wire color code diagram & start look from the fuse on..good luck.

tachicardia · Aug 4, 2016

07GtS197 said:
Have you tried resetting the airbag computer by jumping the gray connector under the glove box? It could be nothing or it could be something like a bad ground or the airbag computer is bad.

Yup, but without a fuse in place the 12 fault code won't go away. I'm going to work my way around the ground wires to see if that might be ut, thanks.

tachicardia · Aug 4, 2016

Mustanger said:
if the fuse blows instantly that indicates a hot wire to ground short...like a skinned wire touching metal or some other failure like that. get a wire color code diagram & start look from the fuse on..good luck.

Yea, I'm thinking the same. I was hoping someone else might have experienced this and had a direction to point me in. A quick Google search shows one other person had a similar scenario but there was never a solution posted. Thanks!

ttocs · Aug 5, 2016

we need to find out exactly what circuits are on that fuse and then isolate them by disconecting them and then inserting the fuse to see if it pops with out that piece in the circuit. I would use my manual but its for 94/95 and I am sure its different by 97. Anyone have an orange OEM manual?

tachicardia · Aug 5, 2016

Thanks ttocs. It's a 96 if that matters?

According to the veryusefulinfo.com page the fuse should be hot all the time (good news) and it identifies 2 areas to check for constantly blowing fuses. The diagram is below - does anyone know where those grounds are located?

lwarrior1016 · Aug 5, 2016

Man, I had this same code and problem on my 98. I never got it fixed though, and honestly I quit looking for it. Im interested to see what you find. Ive been through my whole wire harness and I dont have any shorted wires. I wonder if the module itself is bad and shorting internally?

tachicardia · Aug 5, 2016

Ugh - that's not promising! Haha. I guess at the least I should find out if the hot wire is coming from the module or from the engine bay, that should help narrow down the module as the issue. Or maybe disconnecting the airbag module harness, that should eliminate any power from the module at least, then check to see if the fuse socket is still live.

ttocs · Aug 5, 2016

in the orange manual there is a spot that shows where all the grounds are. I think the abs is under the console isn't it? I would look there for the closest ground and trace some wires to see what you find. You can also try disconnecting it and then insert the fuse to see if it blows as if it does not then you know its the abs module.

lwarrior1016 · Aug 5, 2016

ttocs said:
in the orange manual there is a spot that shows where all the grounds are. I think the abs is under the console isn't it? I would look there for the closest ground and trace some wires to see what you find. You can also try disconnecting it and then insert the fuse to see if it blows as if it does not then you know its the abs module.

Air bag module, right?

ttocs · Aug 5, 2016

yes sorry

aj351w · Apr 28, 2023

Anyone ever find a fix for this, I have the same issue with my 95 Cobra...

optionizerSS · Apr 28, 2023

Just bought a 1995 GT the other day with the air bag light on. Has a code 12 set so same thing for me, researching

ttocs · Apr 28, 2023

tachicardia said:
Thanks ttocs. It's a 96 if that matters?

According to the veryusefulinfo.com page the fuse should be hot all the time (good news) and it identifies 2 areas to check for constantly blowing fuses. The diagram is below - does anyone know where those grounds are located?

did we ever see what code 13 and 14 was since it says that might cause it to blow the fuse?