Hi guys,

Not trying to flog a dead horse with this one but I'm kind of backed into a corner with it.

I've had an MOT done and one of the issues to come up was for the SRS light (airbag light). I've followed previous advice from other threads and discovered it's an issue with the passenger airbag exclusion switch (pic of error attached). More digging on here has helped me realise how common a problem this has been for people. I need to get this issue sorted ideally within 10 working days so I'm not paying for another MOT.

I've seen lots of talk about obtaining a new wiring loom. However, I've had absolutely no luck with this.

I tried contacting FIAT using the number on their site but all the department selections were just sending me in circles. Next, I've got into contact with the local FIAT dealer in my area but their parts department is saying that they can only offer a new exclusion switch to try (fairly confident this won't work and will cost £60 for the pleasure). The guy there would only offer full electrical looms for all the electrics and said he'd never come across somebody asking just for a loom for the exclusion switch (he'd been there 3 years).

Is anybody with previous experience able to tell me how they obtained a loom and who they spoke to exactly. Is anybody able to link any third-party kits I could use (had no luck searching myself). The car still has a valid MOT at the moment so if anybodies had a good experience with a dealer in their area I'm happy make the drive there.

Failing this, is there anyway I can try and keep the light at bay long enough for it to pass any MOT? Maybe just attempting to check all connections and giving them a clean? Then, when I have more time (and patience), I can look into getting this fixed for good!

Any and all suggestions are welcome; I'm kind of at my wits end with this right now.

Switch iirc rarely the issue iirc it# power all night the loom and am fairly confident a short loom was he. Answer to my. Sons 8v and daughters 16v 1.2’s. I’d need to get her to dig around her car box but iirc I bought the loom from fiat desira (Norfolk way?) for around £20 but could of course be way off base and sure a more knowledgeable member will chip in

6 years ago there were all sorts of theories about the reason behind this fault, from it being overloading the glove box to the switch being faulty, more recently I saw someone suggesting turning the switch on and off a whole bunch of times and that would fix it.

The problem was at this time I had the same fault in my 2004 mk2b and nothing was helping so I investigated the mythical wiring loom and found it exsisted, obtained the part and the part number after an argument with the dealer (ironically Desira in Norwich) who after I got Fiat UK involved relented and agreed to sell me the part.

I then made this video.
[ame]https://youtu.be/ZGidfGQtO9Y[/ame]

As an electrical engineer I knew it wasn’t the switch or the contents of the glove box,what the wiring patch confirmed is what I thought, there is a wire comes from the ecu, to the switch then is connected to ground, it does not return to the airbag ecu.

What the patch does is overcome a problem that occurs often in fiats in several areas because of using cheap wiring, that is to say they originally used a common ground for the switch, the ground went back into the dashboard wiring loom and was connected to the same wires as a whole host of other electrical devices in the dashboard.

This means that if the ground is weak stray voltages can travel back into the airbag ecu looking for ground and these stray voltages are what trigger the airbag ecu to think there is a fault.

So what the wiring loom does, and if you watch my video you’ll see, is separate the earth/ground from the switch to the dashboard wiring loom ground and connects it to its own independent ground away from other devices to avoid that potential for noisy stray voltages.

If you want to fix this problem and you are happy with working with electrics, you can fix the problem fairly easily by cutting the ground wire for the switch, from the dash board loom and adding your own ground in its place, connected to the car body somewhere away from other ground connections. This should solve your problem and avoids having to fight with dealers to sell you the part, alternatively show the dealer the video on your phone at the parts counter, which has the part number, then it will be difficult for them to deny its existence.

As you’re not playing with the wiring to the airbags and this is in essence a dumb switch, if you get things wrong you’ll have the same airbag warning you already have and the system will be inactive.

If your not confident with electrics definitely either follow the video or pay a professional

I do wonder if you got a scrappies car loom for the feed to the switch - and cut the earth feed and go else where
In thoery thats all the replacement loom is....

Leaving the old loom intact and yea good to go

Ziggy

just done that cut wring put new earth in. checked wring with meter all fine