(T) Air bag with a difference

Well it had to happen. I've escaped the airbag blues until now but today it happened. "Airbag failure" followed by STOP ENGINE and red airbag light
Nothing new there. Every car I've owned in the last 10 years enjoys has done the same. Joy!

Finding a solution is taxing me though
It's not the wires and connectors under the seats, they make no difference no matter what i do with them. It's not the orange airbag connector in the glove box and there's no effect from the one in the boot either, So I'm in unchartered territory now

It's very consistent though- if you sit in the driver's seat then no problem- no warnings. As soon as you sit in the passenger seat (no you don't even need to move the seat) the airbag warnings start. Get off the seat and the warnings go off. Bizarre. The "Passenger air bag switched off" light comes on too. Any experiences-ideas?

Question- If you turn the Passenger air bag off manually and then an adult sits in the passenger seat is it normal to receive an airbag verbal warning? I haven't ever done it so I don't know

doh! i was expecting to see a pair of t*ts considering the thread title

Well I carry a little passenger in the passenger side regularly and disarm the air bag the only warning I get on my 1.6 is a red diagonal line through the symbol telling me that that side is not operational hope that helps

Right, thanks Phil. I've been getting that symbol flashing at me for no reason on occasions lately. Think I might investigate the on off switch tomorrow

could it not be the preasure sensor on the passenger seat that is the problem

It's a good point Stripey but the way I'm thinking -it's sensing whether there's anyone in the seat or not quite correctly. There's so little information on Stilo airbag systems but does it even have a pressure sensor? I think it senses more than that - more than just an on/ off seat occupied pressure sensor- I think it works out how heavy/big you are by capacitance across the occupant's bum so it knows whether to and how to deploy the airbag in stages

The airbag ECU is sending out a square wave osciilation signal to the seat sensors and there are multiple sensors across the seat. Capacitance change means a change in the square wave to a point where it triggers the airbag ECU to "OK to fire when necessary"

With a simple pressure sensor in the seat the airbag system dosn't know whether there's an adult there on the seat or just something heavy like shopping so it might deploy an airbag needlessly in a collision. But a person has capacitance which can be measured between two electrodes in the seat bum area contacting their body and give an indictation of presence and size. Lardass? Cute bum? Hmmm Clever stuff

The "Passenger air bag is switched off" amber warning light has been flashing quite a bit of late so I'm gonna check the switch there first thing

This sounds so similar to what I had - I ended up having the passenger pressure sensor replaced twice under warranty [the first replacement one was faulty], and never had any issues since.

Tell me more Stu. What warnings did you get? Did you have the "Pass seat air bag" light flashing now and again? Did you have the red air bag light failure? Was it the same after the first replacement or just dead?

Hi decks
If you disconnect the socket under the seat there is a link inside the plug to give a closed circuit ie does not know that the rest of the circuit as been disconected then see if you have the same problem with the lights. i think!
if the lights out then the poblem is the seat.

The passenger seat in the three door causes a lot of headaches. Mines being playing up lately.

Hi SS1
Yes the problem is certainly with the seat! HA!
There's 3 connectors under the seat
orange- side airbag leave alone
grey -seat occupant classification sensor- (pressure or capacitance sensor- don't know which- but it's not a simple bums on seat -on off pressure sensor- having doubts about this one
white - seat belt conected/unconnected

I shall do some tests with the seat bum sensor. Thanks for input every scrap of experience helps

We have seen a pic of your space shuttles [feet] in the mod for more foot space to the pedals so do we get a shot of your bum now Decks

I recently had a problem with my airbag doing the same sernario! I went for the connectors under the seats first.. unconnected and then reconnected to make sure there was no loose contection. Then the one in the glove box.. i also took the fuse out the fuse block and put a new one in.. and it still didnt maka a difference so i disconnected the battery for a while to reset the ecu. When i connected the battery back up again, i still had the same problem. Left it for a while and came back and hey presto all gone

There is some sort of weight in the seats im lead to believe which can affect the airbag sensors not quite sure how it all works... i know there was a thread were some guys kept getting the airbag warning coming and going and found he didnt have this in his seat and as soon as it was rectified all

Yes that's right Rob he had changed his seats to leather and the passenger side one didn't have the bum on seat sensor so he took it out of his original one and fitted it into the leather seat and he said that sorted it To be honest all these seat sensors are a pain in the arse [excuse the pun why on earth do fiat or any manufacturer bother their nothing more that a bloody gimmick and to us a bloody nuisance

Totally agree phil.. next time i fink ill go for a car without them! forgive me for saying it but ive been looking at woundering further a field out the fiat circle but its italian metal so its alright just gota waiting for me 21st, dam insurance