Airbag wiring.

[lacroupade]

Well, who said fettling was fun! :doh

I was looking to swap the leather interior from the T2 thats staying - because I hate leather seats, period - for the cloth seats in the one thats going.

After ripping the fronts out though I have a little trauma and I'm hoping someone who knows autoelectrics better than me can help.....

The cloth seats that I've pinched from the MkIV have active head restraints and seat airbags, whereas the leather ones from the MkIII don't. Thats fine for the MkIII with its donor cloth seats, but when I put the leather ones into the MkIV of course I've had to tape up the connectors for the seat airbag/head restraint.

BUT when I turn the ignition on the airbag light stays on, flashing slowly.

So, not wanting to do the dirty and discaboobalate the warning light, is there any way I can, for example, short the wires out or something. I haven't dared try it in case it sets the other airbags off!! Not clear what the check light is looking for, continuity or something else.

And to confuse matters, there are two plugs on each seat position, one with a pair of yellow wires and one with a single black wire......

Anyone got any educated advice before I have to bite the bullet and put the bloody things back again

 

[solarman216]

I do not think the plugs are going to be looking for continuity or even a set resistance, it is more likely a digital signal to establish the airbag is in a functioning state, do not think there is a way round this one other than remove the bulb, but then it will not show for the MOT, on a Citroen Xantia I had a light staying on problem and found a multiway yellow plug near the gearlever which when disconnected stopped the light working and just realised they did not pick it up on MOT, incidentally have you ever seen a bag go off, you do not want to be in the car when it does, we set them off to make them safe for scrapping, Rick

 

[Terranoman]

look in the download section at air bag resetting. Give that a try first and see if the light comes back on after a reset.

If it stays off then these no need to mess about with the wires.

 

[rayf3262]

It does check for open circuit/short to ground and others to the ABag module, so you are going to have to place a resistor (of currently unknown value) in there to keep the air bag diagnosis unit happy!

 

[solarman216]

It does check for open circuit/short to ground and others to the ABag module, so you are going to have to place a resistor (of currently unknown value) in there to keep the air bag diagnosis unit happy!

if that is the case, please do not be tempted to use a multimeter to measure the resistance of the air bag as it could just fire the mechanism, I will measure a steering wheel bags resistance tomorrow while in a safe place, it may just give an idea of the range to be looking in, Rick

 

[rayf3262]

if that is the case, please do not be tempted to use a multimeter to measure the resistance of the air bag as it could just fire the mechanism, I will measure a steering wheel bags resistance tomorrow while in a safe place, it may just give an idea of the range to be looking in, Rick

A DVM will be safe, that will not pass enough current to "fire" anything.

The diagnostic unit operates in a similar fashion to the lamp check systems on other vehicles, it sends a short pulse then checks for a specific current so enabling it to detect many anomalies.

 

[lacroupade]

Thanks for the replies chaps - sounds at the moment like I might just have to reinstall them as the risk of setting something off and ruining the seats especially isn't worth it.

But out of curiosity, what are the two connectors for do you think....one has just a single black wire, the other has two yellow/coloured wires....not sure if there are separate circuits for the seat airbag and the head restraint.....

I'll try the airbag reset though in case that does something :thumb2

 

[solarman216]

A DVM will be safe, that will not pass enough current to "fire" anything.

I was being cautious as are the manuals that state you should not use a meter to test for resistance on an air bag system, I agree I do not think that there is enough current to set one off, but combined perhaps with static? I do not know but will try and find out tomorrow, I have only ever applied 12 volts, what I do know is you do not want to be on the receiving end of one when it fires, the passenger bag for example if placed face down and fired lifts the metal box it is carried in 15 feet off the ground, Rick

 

[solarman216]

Thanks for the replies chaps - sounds at the moment like I might just have to reinstall them as the risk of setting something off and ruining the seats especially isn't worth it.

But out of curiosity, what are the two connectors for do you think....one has just a single black wire, the other has two yellow/coloured wires....not sure if there are separate circuits for the seat airbag and the head restraint.....

I'll try the airbag reset though in case that does something :thumb2

the yellow ones are air bag and they only need two, I guess the other is the head restraint, but do not really know as I have not bangered a late enough model to have them, Rick

 

[lacroupade]

I was being cautious as are the manuals that state you should not use a meter to test for resistance on an air bag system, I agree I do not think that there is enough current to set one off, but combined perhaps with static? I do not know but will try and find out tomorrow, I have only ever applied 12 volts, what I do know is you do not want to be on the receiving end of one when it fires, the passenger bag for example if placed face down and fired lifts the metal box it is carried in 15 feet off the ground, Rick

and yet eBay still allows people to sell and ship steering wheel airbags.....bloody amazing.

the yellow ones are air bag and they only need two, I guess the other is the head restraint, but do not really know as I have not bangered a late enough model to have them, Rick

What do you think would happen if I just shorted the two wires (the seats are no longer present of course so that airbag can't go off......

 

[solarman216]

and yet eBay still allows people to sell and ship steering wheel airbags.....bloody amazing.



What do you think would happen if I just shorted the two wires (the seats are no longer present of course so that airbag can't go off......

no the one in the seat cant but what about the steering wheel one? wait till I get a rough idea on resistor value tomorrow, once I have a value, I have hundreds of all value resistors, so I can then disconnect my wheel air bag connect a resistor of the same value that I read from the bag and see if it stops the light, Rick

 

[lacroupade]

no the one in the seat cant but what about the steering wheel one? wait till I get a rough idea on resistor value tomorrow, once I have a value, I have hundreds of all value resistors, so I can then disconnect my wheel air bag connect a resistor of the same value that I read from the bag and see if it stops the light, Rick

That would be terrific. Thanks. :thumb2

and next time you blow up an airbag, video please! :lol

 

[solarman216]

Well not a good day really, first the air bag has a shorting link built into the connector so to read the resistance you have to cut the wires, the DVM did not set it off but got 2.7 ohms one way and 3.3 ohms the other so it is not straightforward, disconnected the bag on my car and reconnected it after getting the flashing AB light but after reconnecting the light still flashes so not able to do a resistor test until I can reset it, and it seems I need consult II to do this I tried the ignition on for 7 secs then off three times then on but did not clear it, so unless anyone can say otherwise it will have to wait till I obtain consult II, however will set the old bag off shortly with video, so next question how do I load video, Rick

 

[lacroupade]

Well not a good day really, first the air bag has a shorting link built into the connector so to read the resistance you have to cut the wires, the DVM did not set it off but got 2.7 ohms one way and 3.3 ohms the other so it is not straightforward, disconnected the bag on my car and reconnected it after getting the flashing AB light but after reconnecting the light still flashes so not able to do a resistor test until I can reset it, and it seems I need consult II to do this I tried the ignition on for 7 secs then off three times then on but did not clear it, so unless anyone can say otherwise it will have to wait till I obtain consult II, however will set the old bag off shortly with video, so next question how do I load video, Rick

well i think you worked that one out Rick LOL.....and its made me decide to junk the idea frankly! :thumb2

 

[solarman216]

well i think you worked that one out Rick LOL.....and its made me decide to junk the idea frankly! :thumb2

I do not blame you on that one, best regards Rick