Technical Airbag failure / control unit faulty

[smurphy661]

Hi,

The error message 'Airbag failure' has appeared on my dash along with the warning light. I tried disconnecting the battery, but this did not clear the error. I plugged in the Multiecuscan and attempted to clear the error code, but this did not work either.

The error code i get from Multiecuscan is B1001 - Control unit faulty - no signal - fatal - light on
There is also an error code B1001 - Battery Voltage - Signal high - Fatal

The description of the fault is - 'The reason for this fault is that ECU did not receive signal from the sensor.'

Does anyone know how to fix this? My first thought is to locate the airbag control unit and check that none of the cables have come loose - does anyone know where i can locate the airbag control unit?

 

[smurphy661]

Hi,

The error message 'Airbag failure' has appeared on my dash along with the warning light. I tried disconnecting the battery, but this did not clear the error. I plugged in the Multiecuscan and attempted to clear the error code, but this did not work either.

The error code i get from Multiecuscan is B1001 - Control unit faulty - no signal - fatal - light on
There is also an error code B1001 - Battery Voltage - Signal high - Fatal

The description of the fault is - 'The reason for this fault is that ECU did not receive signal from the sensor.'

Does anyone know how to fix this? My first thought is to locate the airbag control unit and check that none of the cables have come loose - does anyone know where i can locate the airbag control unit?

Sorry the second error code is B1002 - Battery Voltage - Signal high - fatal

 

[124spiderman]

Just happened to mine. Exactly the same issue. Airbag control unit fried.
Located under the air condition unit above tunnel next to footwell.

 

[smurphy661]

Just happened to mine. Exactly the same issue. Airbag control unit fried.
Located under the air condition unit above tunnel next to footwell.

Thanks for your reply. Yes that read out looks exactly the same as mine. Did you have to remove the whole centre console to get to the air condition control unit? I did that once before for another issue and I remember it being a bit of a nightmare and taking quite a long time

Did you repair yours or take it to a garage for repair?

 

[124spiderman]

Garage diagnosed the problem. But yes unfortunately you have to remove the plastic console to get to the connector and bolts as it’s attached to the top of the transmission tunnel. Bitch to get to. I’ll keep you posted as mine is in progress. Happened yesterday. Can’t get a ne one so lucky I found one at a breakers yard.

 

[smurphy661]

Garage diagnosed the problem. But yes unfortunately you have to remove the plastic console to get to the connector and bolts as it’s attached to the top of the transmission tunnel. Bitch to get foto.

Yeah what a pain. Are you going to fix yours yourself? As this is such a pain to get to I am half tempted to take it to a garage, but have no idea how much something like this would cost.

 

[124spiderman]

You guys in the Uk are lucky as there a guys who can reset/fix them.
We have no such skill here except beer drinking

 

[TP Bravo 09]

Hello, I'm also having warning light issues that seem to be due to a dodgy module however I can't find anywhere to get the part number and don't want to take apart my console without knowing the sticker will still be on my original. Main dealer won't give it out as they want to sell original parts so if you have any good ideas of where I can find it I'd really appreciate it. Mine is a 2009 1.4 T Jet Dynamic

 

[124spiderman]

update: managed to find a second hand unit and problem is now fixed. Just need to do a proxy alignment now as the main body computer has failed to recognise the replacement unit and my odometer is flashing.
Takes longer to remove the console. As it’s a big pain in the ( * ) to get to under the heater unit. After the plastics are removed it’s is easy to replace provided you disconnect the battery first and wait 15 minutes before you disconnect it. Then remove 3 bolts that holds it to the car body. Replace is reversal. 30 minute job.

 

[124spiderman]

Well ok then……start car up today and airbag warning light stays on ..
Odometer flashing. ?. WTF? all was well for 3-4 weeks. Can it be possible it may need another proxy alignment?

 

[smurphy661]

Well ok then……start car up today and airbag warning light stays on ..
Odometer flashing. ?. WTF? all was well for 3-4 weeks. Can it be possible it may need another proxy alignment?

Did you get this working again? I think I may have to do the same as you and buy a second hand unit and do a proxy alignment - did you do the proxy alignment yourself? If so how?

Update on my situation -

- I took my car to the local garage - they couldn't fix it and told me to contact Fiat or a specialist
- I took the airbag ECU out of my car myself (have to remove centre console and glove box and the ecu is held down with three bolts - two are access from the passenger side and the other from the drivers side. Disconetect the battery 1 hour prior to touching the ECU. The ECU has two cables plugged into it)
- I sent the ECU to www.autotronics.co.uk who quoted £226 for the repair including return postage.
- www.autotronics.co.uk then called me to say that they cannot repair the ECU
- I then called CrashData.co.uk and asked if they would be able to repair it - they said that they can't and my only option would be to buy a new one from Fiat and have them code it to my car
- I called Fiat for a quote - £1080 for a new ECU then labour on top for fitting and coding to the car. They are going to give me a quote for labour, but this sounds like it will be more than the car is worth.

If anyone has any experience with buying second hand airbag ECUs and having them proxy aligned to their cars - let me know

Thanks

 

[124spiderman]

The used control units are not compatible with the body computer. You need to install brand new unit and code it to the car. And after that still no guarantee that it’ll work.
The part costs over $2200 AUD SO Sadly I had to get rid of the car as I couldn’t get a roadworthy certificate here and Was too costly to repair with no guarantee.
I guess it’s called “built in obsolescence”. It’s what fiat does best. Just like they did in the 70’s and 80’s with rust. I guess it’s their way of getting rid of their older cars from roads.
Disappointing as I loved that car.

 

[124spiderman]

Did you get this working again? I think I may have to do the same as you and buy a second hand unit and do a proxy alignment - did you do the proxy alignment yourself? If so how?

Update on my situation -

- I took my car to the local garage - they couldn't fix it and told me to contact Fiat or a specialist
- I took the airbag ECU out of my car myself (have to remove centre console and glove box and the ecu is held down with three bolts - two are access from the passenger side and the other from the drivers side. Disconetect the battery 1 hour prior to touching the ECU. The ECU has two cables plugged into it)
- I sent the ECU to www.autotronics.co.uk who quoted £226 for the repair including return postage.
- www.autotronics.co.uk then called me to say that they cannot repair the ECU
- I then called CrashData.co.uk and asked if they would be able to repair it - they said that they can't and my only option would be to buy a new one from Fiat and have them code it to my car
- I called Fiat for a quote - £1080 for a new ECU then labour on top for fitting and coding to the car. They are going to give me a quote for labour, but this sounds like it will be more than the car is worth.

If anyone has any experience with buying second hand airbag ECUs and having them proxy aligned to their cars - let me know

Thanks

The used control units are not compatible with the body computer. You need to install brand new unit and code it to the car. And after that still no guarantee that it’ll work.
The part costs over $2200 AUD SO Sadly I had to get rid of the car as I couldn’t get a roadworthy certificate here and Was too costly to repair with no guarantee.
I guess it’s called “built in obsolescence”. It’s what fiat does best. Just like they did in the 70’s and 80’s with rust. I guess it’s their way of getting rid of their older cars from roads.
Disappointing as I loved that car.

 

[smurphy661]

The used control units are not compatible with the body computer. You need to install brand new unit and code it to the car. And after that still no guarantee that it’ll work.
The part costs over $2200 AUD SO Sadly I had to get rid of the car as I couldn’t get a roadworthy certificate here and Was too costly to repair with no guarantee.
I guess it’s called “built in obsolescence”. It’s what fiat does best. Just like they did in the 70’s and 80’s with rust. I guess it’s their way of getting rid of their older cars from roads.
Disappointing as I loved that car.

Latest update on my situation -


I bought a used Airbag ECU from eBay for £180 ish. Before I started the replacement my battery went flat. I have read on multiple forums for different car types that flat or dying batteries can cause the airbag ECU to die so this could well be what cause it for me.

I took out the old dead airbag ECU and replaced it with the one from eBay (as before i disconnect the battery 30 minutes before starting work on the ECU and reconnected once the replacement ECU was fully connected).

The airbag light and warning was gone immediately, but the mileage odometer was flashing as expected. I connected to the car with Multiecuscan and made a copy of the Custom Proxi and saved it on a Notepad file just in case i need to go back (instructions for this here - https://www.fiatforum.com/guides/backup-proxi-file-on-mes.875/)

I then cleared the airbag error codes and finally ran a Proxi Alignment.

This has fixed the issue for me.

I am hoping that i do not have the same issue as you 124spiderman - did your 2nd hand airbag ECU have the same model numbers as the original and did you change the battery at the same time? I've read that both can cause issues.

One other note, i had a 'U0422 - Inertia function' error that has been on the car for 9ish years that i could not clear. This did not prevent my from running the Proxi alignment.

 

[124spiderman]

Glad you were able to sort it. I also found a second hand unit and it worked for about 2 weeks before the same issue. Direct part replacement. Magneti Marelli same part number. I also had the original unit reset and it failed after a week. Did the proxy. Battery was new. Keep your finger crossed.

 

[smurphy661]

Ah wow that's not good. Thanks for the update. It's been just under 3 weeks now and so far so good. I'm hoping I get lucky with my one - I will post back if it goes again.

 

[Drei]

Ah wow that's not good. Thanks for the update. It's been just under 3 weeks now and so far so good. I'm hoping I get lucky with my one - I will post back if it goes again.

So any news? I am in the same situation and would hate to throw the ca away just for one stupid part. Can you wipe a 2nd hand unit then clone it with a copy of your data?

The annoying part is that mine failed the day before the MOT... at least if it was after I could still use the car to get to and from a garage. Right now I just wanna fix it and get through the MOT.

 

[smurphy661]

So any news? I am in the same situation and would hate to throw the ca away just for one stupid part. Can you wipe a 2nd hand unit then clone it with a copy of your data?

The annoying part is that mine failed the day before the MOT... at least if it was after I could still use the car to get to and from a garage. Right now I just wanna fix it and get through the MOT.

Hi,

Yes the car is still fine - no airbag issues. I got the 2nd hand unit from eBay from a seller in Spain that refurbishes airbag units - the user name was francao1525

I just did a search and he has the same unit that i bought.



My advice to you -

- Buy a 2nd hand unit with exactly the same model / part numbers
- if your battery is old or could be near end of life - get a new one
- Follow all the other instructions that i left in the thread and you should be fine. (see main ones below)

I took out the old dead airbag ECU and replaced it with the one from eBay (i disconnect the battery 30 minutes before starting work on the ECU and reconnected once the replacement ECU was fully connected).

The airbag light and warning was gone immediately, but the mileage odometer was flashing as expected. I connected to the car with Multiecuscan and made a copy of the Custom Proxi and saved it on a Notepad file just in case i need to go back (instructions for this are here - https://www.fiatforum.com/guides/backup-proxi-file-on-mes.875/)

I then cleared the airbag error codes and finally ran a Proxi Alignment.

This has fixed the issue for me.