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Discussion Starter #1
My airbag light comes on and stays on.
The manual says the center airbag sensor stores fault codes. I am wondering how to check the codes stored in the center airbag sensor?
Do you get a regular code reader and plug it in under the dash?
 

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Discussion Starter #6
I'm not looking to clear any codes just yet. I want to retrieve the stored codes first so i can address why the light is on in the first place.
I have not spilled anything on the brake, no.
 

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1997 Corolla
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This is how my 1997 Toyota Repair Manual says to retreive the codes.

(a) Turn ignition switch to ACC or ON position and wait approx. 20 sexonds.

(b) Connect terminals Tc and E1 of the DLC1. (You can use a bent paper clip to do this. The DLC1 is a little connector located near the left front strut tower under the hood. You open the cover and the terminals are labeled on a sticker on the underside of the cap.)

NOTICE: Never make a mistake with the terminal connection position as this will cause a malfunction.

Once you do this, the airbag warning light will flash out 2-digits codes. For example code 31 would be 3 flashes, a 1.5 second pause, then 1 flash. Then a 2.5 second pause followed by the next 2-digit code. There will be a 4 second pause before the codes repeat.

Report back your codes.
 

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Discussion Starter #8 (Edited)
It came back with a 31 code.
The light doesn't come on everytime i start the car. Its only occasionally. I am wondering if it has anything to do with the driverside seatbelt? If I put my seatbelt on during the dings just after I start the car the light goes off. If I put my seatbelt on before I start the car or after the dings are done it stays on.
 

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1994 Corolla DX
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DTC 31 - Center Airbag Sensor Assembly Malfunction

Was that the only code? The FSM states that if it's output in conjunction with any other code you should address the other code first and reset, then retest to see if 31 also went away.

It's not very helpful on what to do if not, other than "replace center airbag sensor assembly".
 

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Discussion Starter #10
No there was no other code.
The light doesn't come on everytime i start the car. Its only occasionally. I am wondering if it has anything to do with the driverside seatbelt? If I put my seatbelt on during the dings just after I start the car the light goes off. If I put my seatbelt on before I start the car or after the dings are done it stays on.
 

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1994 Corolla DX
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Weird. Maybe some issues with wiring harness? Perhaps pop off center console and check connections, test for ground continuity, etc.
 

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Discussion Starter #13
Maybe I just needed to threaten my car with tools.
I turned the key on and off over 10 times in case the computer needed to log the error multiple times before the light stayed on. It has stayed off so far.
I'll keep you posted on whether it comes back on or not.

It's the ghost light!! ha ha ha
 

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1994 Corolla DX
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Heh. My bet is it will be back. Intermittent issues are challenging to diagnose and they never "just go away" unfortunately. You're on the right track though trying to find what pattern might trigger it, if any.

As it pertains to ground continuity what I was after is whether one of the wires had insulation issues and somehow touching ground when it shouldn't. You'll need a good wiring diagram and an ohm-meter. DannoXYZ is the electrical gremlin chaser here so I'm sure he's got a ton of other suggestions for how to track this down.
 

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Yes, code 31 is airbag sensor assembly malfunction. The troubleshooting steps are to check for voltage at the IGN (powered from IGN fuse) and ACC (powered from CIG fuse) terminals of the airbag sensor assembly. (You'd need some diagrams to do this.)

After that it says to clear the code then turn key from LOCK to ACC or ON at least 5 times, waiting 20 seconds between each position. Then recheck for codes.

If the code comes back, replace airbag sensor assembly.

But it could be an intermittent wiring problem like 94RollaDad mentioned.
 

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2006 Corolla XRS
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It's also possible that the seat belt buckle malfunction.

Does it stick at all? Grime and dust can get in there and gum it up. That's where I would start.
 

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I think you might be onto something with the seat belt thing! Correlations often mean something.

The million dollar question is: Do, and if so, how, do the seat belts interact with the airbag system?
 

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I think you might be onto something with the seat belt thing! Correlations often mean something.

The million dollar question is: Do, and if so, how, do the seat belts interact with the airbag system?
The mechanism in the buckle gets all nasty and cruddy over time. Drinks and food, along with dust will get inside the buckle and eventually trick the sensor, light, crash sensors, ad computer. Just be thankful the airbag didn't deploy.

The simplest test method is to clean out the buckle and then test it. If the light is still on, then the buckle should be replaced.

From here, I would look locally to find someone whose either parting out a good one that was not involved in any accidents. Then again, I don't know if the buckle is considered to be good even after an accident.

My understanding of the airbag system is this. The buckle sends signal when seatbelt is connected. The airbag computer will do its thing and verify issues thru it's system checks. Then the airbag computer will report the code to the ECU once stored and recorded then illuminate the airbag light. I can be wrong, but that's my assessment.
 

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The mechanism in the buckle gets all nasty and cruddy over time. Drinks and food, along with dust will get inside the buckle and eventually trick the sensor, light, crash sensors, ad computer. Just be thankful the airbag didn't deploy.
I would think that Toyota would've made darned sure that something as inevitable as a dirty seat belt buckle would never cause a deployment of air bags.

My understanding of the airbag system is this. The buckle sends signal when seatbelt is connected. The airbag computer will do its thing and verify issues thru it's system checks. Then the airbag computer will report the code to the ECU once stored and recorded then illuminate the airbag light. I can be wrong, but that's my assessment.
Perhaps the buckle is what arms the airbag system on the passenger side, rather than a sensor in the seat to detect weight on the seat, which is what I believe they use today.
 

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The weight sensor in the newer cars and trucks are to determine deployment.

Supposedly, and I have seen it first hand. The airbag becomes a deadly object to individuals that does not meet the requirements for being less injured by an airbag. Based on my own research, airbags were developed in the 50's and was designed to protect male drivers over 120 lbs. They weren't widely used until the late 80's and early 90's industry wide.

When I saw it, a friend was in the front passenger seat. Going roughly 20 to 0 in under 10 feet. The airbag deployed, but the friend was thrown like a rag doll. Passenger was 4'10" and under 120 lbs. The airbag barely touched the face, but got burn marks from when the airbag first deployed.

Why does this info matter? Because the early systems were very sensitive and were prone to failure of deployment when really needed in an accident.

The buckle will always have a large entry to allow dust and debris to interfere with the buckle. In the 9th gen forum, there are a few threads in regards to the passenger side airbag for Corolla and gen 1 vibe and matrix. Some owners have noticed sticking in the buckle and the error was cleared when the buckle was replaced. How it's tied into the airbag system is unknown to me.
 
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