Technical Airbag light

[nilenelson]

Hello all,

Can anyone help me get my 98 Barchetta back on the road, it's an MOT failure due to the airbag light staying on. I've just spent almost the entire day with an auto electrician, seats removed, connectors replaced with soldered wires etc etc, but still the light is on. The ECU is now suspected as the faulty component, part number 46443798. Does anyone have a spare to try or any other suggestions please?

Many thanks

Chris - tel 01798 867768

 

[Ilkka]

The light will stay on even when the fault is fixed until the error code is cleared from the memory.
So try to find a reader and check and reset the codes, most likely a faulty connector under the seat or a drained battery at some point.

 

[StevePD]

Hi Nilenelson,
Try a search on this Barchetta forum for airbag light reset, there is ooodles of info on this problem and how to connect your laptop to the airbag diagnostic plug. Worth a read.
Good luck with resetting it.
SteveD

 

[itaa5x]

there's a VERY quick solution for this- take out the whole speedo unit, like 3screws? and take out the airbag light bulb out - Its less than 3-4minute job in total.

 

[Davefridge]

there's a VERY quick solution for this- take out the whole speedo unit, like 3screws? and take out the airbag light bulb out - Its less than 3-4minute job in total.

Then your MOT guy fails it because then the light didn't come on. A far better bodge is to wire the light in with the ABS light!!

 

[itaa5x]

Then your MOT guy fails it because then the light didn't come on. A far better bodge is to wire the light in with the ABS light!!

Does it even comes on when you start the car? I dunno as Someone had already taken out the bulb for me and I don't have trouble passing any inspection.
Also I got the bulb taken out for ABS and some other functions as well
If I were to put in all bulbs in to my unit it would light up like an xmas tree

 

[Davefridge]

On an English MOT test, all warning lights should come on, then all warning lights ( air bag, ABS, engine management etc.) should go out in 3 seconds.
If they don't, its a fail.

 

[itaa5x]

On an English MOT test, all warning lights should come on, then all warning lights ( air bag, ABS, engine management etc.) should go out in 3 seconds.
If they don't, its a fail.

same here, but I reckon the testers here think it's such an ancient car that it might not even have such an ''feature'' so you can slide away easily. Honestly I know people who has done the same thing with other cars, it just isn't looked at.. If the light shines in all its glory than yes you get raped for it.

Surely there's just not ABS/Airbag lights as such for most of the older cars? How do they pass the MOT? I know my dad in UK had problems with his abs on not so ancient 10year old car, the guys at service Did not fixed the problem itself -instead made the light disappear itself and gave him fresh MOT..

There might be some rules, but the reality is a bit different...
If you cant find the fault I still suggest to remove the bulb..as I seriously doubt you will get a fail for that.

 

[nilenelson]

Thank you all so much for your thoughtful ideas, I am replying to you all here so forgive me please if it rambles on a bit!

Not being very electronic or computer savvy I've taken the car (which failed MOT on airbag light) to an auto electrical specialist who diagnosed "no codes for engine management, airbag codes for seat pre tensioner squibs, voltage low". Unable to clear codes he suspected an ECU fault. Subsequently I've had a 2nd opinion from another electronics man who went deeper into the problem, somehow eliminating the possibility of one of the squibs being a fault, yet the ecu still indicated a fault, so he confirms that the ECU is the most likely culprit.
I think he did manage to clear "low voltage"

I would very much like to get the problem resolved by trying another ECU, mine is a TRW46443798 and I wonder if anyone has a spare that I can buy or borrow to at least eliminate that component, (I can't find another car that uses this ECU) and similarly the "squibs".

If it's not possible to fix this very annoying problem I do appreciate the advice to take out the bulb & use another MOT centre - when I suggested this to the original garage they were not at all impressed, saying they'd fail the old girl again! Can't wait to get back on the road.

Again, many thanks to you ALL.

Best regards

Chris 01798 867768, mob 07710 000214

 

[StevePD]

Hi,
My apologies if you have researched this but have you searched this forum for resetting the airbag light? There is an explanation which has been successful for some, go to search this forum and look for this thread which explains quite a bit.

FIAT Cars > Barchetta > 1997 Barchetta-Connection to MutiECUScan

Sorry if you have tried this but good luck.
SteveD