Airbag Light On

STOP! Most ohm meters run on four double "A" batteries or a nine volt transistor battery. We use nine volt batteries to light off an air bag for demonstrations. An ohm meter will do the same thing.

Also, if you unplug the air bag or the squib, every bright yellow connector has a shorting bar in it to short the two wires together. That is to make the air bag immune to static discharge while the circuit is being serviced or the air bag is being handled. If you are measuring between two connectors, one part is going to have that shorting bar.

No one I know has ever tried to measure a clock spring, which goes against normal procedures. We normally want to verify a part is defective before we order a replacement, but in this case, given the age of the car and the mileage, a bad clock spring can be expected. The wiring is real reliable, so unless a connector has been damaged, don't go looking for something obscure. If the fault code was related to an open squib, replace the clock spring. The additional clue is anything else on the steering wheel will also fail shortly. Typically that is the horn and cruise control. Once the ribbon cable starts to break near one end, all of the circuits will become open real soon.

Air bag failure is pretty much unheard of. The shorting bars are only in places that a lack of them would leave the bag susceptible to static discharge. That means you'll find one inside the connector on the back of the air bag assembly, but one isn't needed on the wire coming out of the clock spring. Similarly, the wire traveling up the steering column is plugged in either on back of the clock spring or at the base of the steering column. In that connector, if you unplug it, the top half has the terminals going to the air bag, so that will have the shorting bar. There's no need for a shorting bar on the lower part that goes to the computer module.

With the air bag set aside, you can safely measure continuity of the squib, or "initiator" wire. If you have tilt steering wheel, moving it repeatedly can cause those wires to break and make intermittent contact. Be sure to move the steering wheel up and down while taking those readings.

If the car was crashed in the past, usually the connector at the back of the air bag melts from the heat of the burning rocket fuel, and that requires replacing the clock spring. If it didn't melt, and someone reused it, check for deformed terminals that aren't making good contact. Be aware too that around that time period, a lot of fault codes for the squib referred simply to a "shorted OR open" condition. A melted or deformed plastic finger on the connector could fail to move the shorting bar away from the terminals. That would cause a shorted condition. To measure for a shorted squib with an ohm meter you have to push the shorting bar away from the terminals.

Also, most Air Bag Computers will shut the system down permanently during that key cycle when an intermittent problem is detected. The problem may correct itself during 99 percent of the time, including while you're taking measurements. In that case, the fault code is all you have to go on This is where we just replace the clock spring as it's the only logical cause of an open squib. We will guess wrong so seldom that in those rare cases, the additional time we need for diagnostics is tiny compared to the time we didn't waste on all the other cars.

Two things. Did you have the battery disconnected with you were doing this? If so, you more then likely missed a connection and it is causing an open circuit. If not, you may have a shorted center airbag sensor.

Here is the testing that you need to run through to fry and find this issue. Let me know if you have questions. Thanks

Okay. We can figure that out but can you give me the exact info on your vehicle? Make, model, year, engine?

We just need to make sure that yours is the same as listed on this post.
Then I can get you the wiring info for your vehicle rather then possibly confusing things with just posting the wiring info on a different vehicle. Thanks

Okay. That is great. What this step is asking you to do is disconnect the battery. Connect the sensor back to the connector. Reconnect the battery and then turn the key on. Does the light come on? It may not stay on but when you turn the ignition on, the airbag light should do its self check where the light turns on and then off. If it stays on that is fine, it just means you have a code.

Sounds like your light does come on when it is connected. If it does then it is asking you to go to the next step and check the fuse and circuit as you may have a wiring issue.

Keep in mind it is important to follow the practice of taking the battery negative terminal off when connecting and disconnecting these connectors. If you don't and you get a quick short or spark the air bag can go off and that will injure you.

Just let me know if this is what is happening when you do this test and we can go from there. Thanks

Yes. Take a look at the attachment. I show you are here where it is saying you need to clear the code, wait the proper amount of time and then check it again. If it comes back you need to replace the assembly.

Hello, I'm Danny.

Just to add my 2 cents here. If you want a good scanner for less money than professional grade I would take a look at Innova brand. Picture below. It's about $250.00 but can be used on both obd1 and obd2. All you have to do is attach an adapter to be one or the other. If you get the right one it covers all systems you mentioned. I bought one myself when my Snap-On scanner was stolen and it works great. Hope this helps and thanks again for using 2CarPros.

You're welcome!
Thanks for using 2CarPros and hope you will use our site again in the future. Happy Thanksgiving.

Danny-

Hi COMERCIALAUTOSERVICE,

Thank you for the donation.

When the ABS indicator is showing, it could be any fault with the sensors and you would have to go into the self diagnostic mode to retrieve the trouble code.

Here are the procedures and there are 2 different types of DLC so you need to check which is the correct one.

Diagnostic Code Check
1. Jump together terminals Tc and E1 of Total Diagnostic Communication Link (TDCL) connector using a jumper harness.

TDCL is located under left side of instrument panel near fuse block.

On alternate models, jump underhood check connector terminals Tc and E1

2. Read diagnostic codes by noting number of AIR BAG warning light flashes.

Normal code indication will flash light twice per second. If a malfunction code is present, first number of code number will equal first digit of a 2-digit diagnostic code. After a 1.5-second pause, second number of code number will equal second digit.
3. If 2 or more codes are present, a 2.5-second pause will occur between codes. After all codes are displayed, a 4-second pause will occur and codes will be repeated. After code has been identified, see appropriate diagnostic code and perform tests as specified.
4. If more than one malfunction code is present, codes will flash from smallest numbered code to highest. If malfunction code is not displayed or is continuously displayed, go to TROUBLE SHOOTING. If AIR BAG warning light remains illuminated and diagnostic code is normal code, a source voltage drop is present. This malfunction is not stored in memory. If power source voltage returns to normal after approximately 10 seconds, AIR BAG warning light will automatically go out.
5. Code 22 is recorded when a malfunction is present in air bag warning light system. If an open circuit is present in air bag warning light circuit, AIR BAG warning light will not glow. Diagnostic codes (including Code 22) cannot be confirmed until warning light circuit is repaired.
6. When a malfunction is present in SRS, malfunction Codes 11 through 31 are displayed. After repair of malfunction, Codes 11 through 31 can be cleared from memory but Code 41 will remain. A special procedure is required to clear a Code 41.

NOTE: On all models when clearing all other codes except Code 41, use Clearing Malfunction Codes (Except Code 41) procedure. On all modes with Code 41 only, use Clearing Malfunction Code 41 procedure.

Clearing Malfunction Codes (Except Code 41)
Turn ignition switch to OFF position. Remove negative battery cable or ECU "B" fuse for at least 10 seconds to clear codes. When reconnecting battery, ensure ignition switch is in LOCK position. If battery is connected with ignition switch in ACC or ON position, diagnostic system may not operate correctly.

Clearing Malfunction Code 41
1. Connect wire probes to check connector/TDCL terminals Tc and AB. See Fig. 13 or Fig. 14 . Turn ignition switch to ACC or ON position and wait approximately 6 seconds. Starting with Tc terminal, apply body ground alternately to terminal Tc and terminal AB twice each, in cycles of .5-1.5 seconds.
2. When alternating probes between body ground, simultaneously release one probe from body ground while applying ground to other terminal. If time interval is too long, Code 41 will not clear. After several seconds, when AIR BAG warning light starts to blink a regular cycle, Code 41 cancellation is complete.