Clock Spring?

@LarryJ
Uh oh, code 31 means a malfunction of the airbag ECU and code 12 means malfunction of either clockspring or ECU. I do not think a new clockspring will do anything since it's telling you twice that the ECU has something going on...

What happens when a ECU is bad is that some capacitor or electronic component in it is failing. Pretty sure it can be repaired, but you need to have it done by a specialized place. Some airbag repair services do pop up after a google search, but you have to make sure you are dealing with a reputable company as I've heard of some people doing very shoddy things to computers and modules.

Also, if you go to a shop where they rebuild salvage title cars, they may be able to direct you to some place that does reset or repair airbag components

 

the weak horn may be caused by a bad relay, fuse or ground. If it was only the clockspring, it wouldn't pop a code 31

 

All you'd need to do is replace the clock spring be careful with pullin the steerin wheel off rent out a steering wheel pulley dont damage the splines, also when u get the clock spring it says on the piece "turn 2.5 turns from the left" but what i found out is your able to turn the cable 5x startin from the furthest left after u turn 2.5 from the left so what i did to get it allinged what install it etc break off the table or unclip the tab then turn it 2.5 to the left making it available for 5 full turns so i turned it 5x around then turned back 2.5 & ended up in the middle make sure not to over do it or u can break the connectors inside or damage it causing early failure to the clock spring. Pm if you need any info help etc

 

Well, if both codes are the ECU, then maybe it won't be so bad. Certainly easier to remove than the clock spring.
Thanks for all the help. I'll start searching for a repair service. I'll be checking the ground and seatbelt too.

 

where is the ecu that's so eazy to change? the clock spring takes only a couple minutes to reach. i replaced mine in like 20 minutes while taking my time.

if you just want to check continuity of the clock spring i don't think you even have to pull the steering wheel. it's the three screws that hold the steering column cover on and the two star screws that hold the airbag in. the yellow airbag wiring loom connects to the back of the airbag and then below the steering wheel is the other end. check for continuity with a cheap ohm meter. if no continuity then your clockspring has broken.
it took me longer to figure out how to change my oil the first time than it did to get to the clockspring. i certainly would rather rule out one possibility than start replacing parts in an effort to fix the problem.

and how can an airbag ecu going bad cause horn issues? you either have multiple simultaneous issues or a singular issue that has two side effects.

good luck.

 

it's located right in front of the shifter, behind the dash panel that is under the radio unit

Bad ECU does not cause the horn issues, it's probably a bad horn relay, fuse or a weak ground

 

Solved! It was a bad battery connection causing the airbag light. I checked the battery and connections early on in my diagnosis, but obviously, not well enough. Put di-electric fluid on the Ground and the light went out. Had to remove the felt pad under the + connection to get a good grip on the post. Can't thank you enough. Send me your invoice, LOL.

 

I spoke too soon. The 31 code reappeared as I move the vehicle. Has to be the clock spring.

 

did the weak horn improve at least?

 

I didn't test the horn. It's an old horn. Could be under-the-hood- issue.

Before pulling the steering wheel I checked the clockspring continuity. It had none. Checked the continuity of the referbished clock spring. It had lots. Managed to get the CS out today, but the refurbished one doesn't fit. The original airbag wires were hard-wired into the backside. I believe I can attach a plug to the wire easy enough. Bigger problem is the cruise control/horn plug doesn't fit the new CS. I guess I'll order another and hope it fits. Don't know what else to do.

Untitled by Larry Johnson, on Flickr

 

Replaced the clockspring with one that had only two pins in the connector, it was the only one I could find. The original had four pins, I assume two were for the cruise control. Now the horn doesn't work and I'm getting the same two codes that I started with; 12 and 31. Checked the replacement CS before installing and there was continuity. Would the CS need to have four pins to work properly in my truck. Could it be the ECU? How would I troubleshoot the ECU. Could the aftermarket alarm that someone installed be causing an issue.

 

Code 31 means a malfunction of the airbag ECU and code 12 means malfunction of either clockspring or ECU. So yes, it is possible the ECU is bad since it is hinting at the ECU twice.
ECU part #89170-35010

as for the horn not working, I guess the wires and the pins on the new clockspring are different (there is slight differences in the wiring over first gen years). Do you have a part number for the one you got?? Also, have you checked your horn relay and fuse?
right clockspring for your 1997 tacoma:
84306-04040(with cruise control)
84306-02020(no cruise control)


here is the trouble shooting procedure for codes 12 and 31, for a 96 truck

 

Good News: Found a replacement ECU and it successfully eliminated the airbag light.
Bad News: Horn still doesn't work and existing clockspring doesn't have cruise control.
I'll check horn relay and fuse as you suggest, but I suspect it's due to the lesser number of pins in the replacement clocks ping. My original has 6, not 4 like I mentioned above.

 

...Better news. Found a clock spring and now the horn and cruise control both work.
The answer to my original question will never be answered because I destroyed the original clockspring during removal, but I believe it was fine. The replacement ECU was necessary.

 

@LarryJ I've been chasing the same problem. air bag light stays on. I've replaced the clock spring, that didn't fix it. Installed a new drivers side seat belt, so that I'd have a working one, that wasn't frayed and shitty looking. Still have the air bag light. My horn and cruse control have always worked, even with the light on. Driving down to Auto Zone tomorrow to pull the codes again. But I have all the spare parts I need. Have a replacement air bag, and the air bag ECU. Just need to figure out which item is causing the problem.

 

To help you problem solve, I have a bad clockspring in one of my 95s and the horn does not work. Well, it does, but only because the previous owner installed a new push button on the bottom of the column. Cruise still functions.

 

My problem has been solved wth replacement ECU and CS.
CippledOldMan, you can read the codes yourself. Read Post #12 in this thread for instructions. Good luck.

 

I copied this picture from post #12. I have a 2003 Limited Crew Cab 4x4 V6 auto. I've been chasing the SRS dash light staying on for awhile. So I thought I'd short out the 2 pins and see what code it's throwing now. Nope, nada, not on my Tacoma. See that little box circled in the pic below. Well my Tacoma doesn't have one anywhere in the engine bay that I can find. I'll edit this later and post a pic of under my hood. So my question now, is does anyone know a decent OBD II scanner that will read most codes, including SRS, Transmission, etc. Not interested in anything overly expensive. I've found some on Ebay, and Amazon for a little over a hundred bucks. Also, going to check the reviews on the ones from harbor freight. Auto Zone doesn't have permissions to read SRS codes on their scanners, or at least that's the story I was told.

 

I use a scangauge in my VW. It won't read or reset SRS codes though. I guess SRS reads/resets have to be done by manufacturer or certified tech. Mine reset itself after the problem was repaired.