I have a 2013 Fiat 500 I’ve owned the car for approximately two years for the last year The battery started to die as it was the original battery so i used to take the battery off the car and charge it up overnight in the house I’ve done this about six times I then developed a fault about six months ago with the dreaded flashing cluster so I sent away for repair when I received it back I refitted the cluster and at the same time fitted a brand-new stop start battery when I started the car up I noticed the passenger airbag light was flashing. With the help of LOVE 500 ( typecastboy ),I decided to send the airbag ECU away for testing and repair the company tested and said your ECU is working fine I have checked all the wiring under the seats and fuses but I still have the flashing light.Any suggestions would be grateful of what to do next thanks

Hi

Have you used any form of plug.in diagnostics..?
Could be the exclusion of passenger airbag..or seat occupancy kit

Charlie

I have been to the local garage who ran a diagnostic test and it came up with : b1000 control unit u1726.. no communication with air bag... control unit u1733 convergence node. When I contacted a airbag ecu repair company on the phone they said it looks like the airbag ecu is faulty with them codes. But when I sent it to them they tested it and all was fine , there was nothing wrong with it . I’ve also noticed that in the menu on the dash I’m missing the facility to turn pass airbag on or off , that part in the menu is missing

typecastboy have you had this problem in the past??

Typecastboy has been helping me with this from the start we both are a little stuck it has been said that it may be the body control unit

Yea, we've spoken on the phone at length and via Whats App but as this happened to me indirectly a few months ago I got stuck then. It wasn't my car but it beat me. I would have delved into it deeper had it been my car as I would have had to.

I think we've come to the conclusion it must be the BCM. It's not the fuse on the BCM for the Airbag ECU but is it a coincidence that this has only happened since he got the failing speedo repaired. The other thing was the battery which was taken out almost every day and charged as it was failing. So i'm thinking the constant in and out of the battery has caused a spike which has blown something. Is it a concidence that it's the passenger airbag though? Really strange.

I think the next thing that has to be done is changing the BCM, ignition key ring and engine ECU and swapping chips or blades in the key. Diagnostics on MES would help but he lives in the Isle of Wight (hence my post recently about anyone with MES there).

I watch this thread with interest as it's baffling me.

Hi to all, here i have a 500, which i got with a non working airbag ecu, got a replacement and connected it to the car, cleared faults and the software said is no faults, the last fault which was there was : non configured .
Tried proxy alignment and it fail on EOL , no airbag lights are on(never), and the fuel cut off and airbag failure warning gone, but mileage still flashing and as i said fails on proxy alignment, maybe i missed a step?
The replacement ecu its a 5wk43908, however the number over the barcode is different

Celefiat said:

Hi to all

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Hi and welcome to the forum.

@typecastboy is the chap here who knows all about this kind of stuff. He'll likely be along soon.

What software are you using? MultiECUScan? When doing a proxy alignment, for the mileage to continue to flash the stages that MES goes through would have to fail on a module. If it's successfully writing to the Airbag ECU and you have no lights on, then it can't be that. Blue & Me working?

Yes i got a shiny multiecuscan, with the set of wirings recomended here.
The airbag lights do not come on at all. No when you switch ignition too.
Howeever, MES connect with airbag ecu and says its no errors, and i went to parameters and it read all of them unless the passenger prescence with stays like waiting and dont show a value, no errors on this ecu or any others, well, blue and me, says aligned ok, but to be fair, did not touch the buttons so maybe.
As i said the ecu was slightly different on that code over the barcode, the proxy alignment says EOL failed on airbag, and no faults on the dashboard unless the flasing mileage(before was airbag failure with the old ecu, and fuel cut off, and the yellow triangle)

Celefiat said:

Yes i got a shiny multiecuscan, with the set of wirings recomended here.

The airbag lights do not come on at all. No when you switch ignition too.

Howeever, MES connect with airbag ecu and says its no errors, and i went to parameters and it read all of them unless the passenger prescence with stays like waiting and dont show a value, no errors on this ecu or any others, well, blue and me, says aligned ok, but to be fair, did not touch the buttons so maybe.

As i said the ecu was slightly different on that code over the barcode, the proxy alignment says EOL failed on airbag, and no faults on the dashboard unless the flasing mileage(before was airbag failure with the old ecu, and fuel cut off, and the yellow triangle)

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Have you still got the old airbag ecu? It would be better to have the crash data wiped and use the same one. It costs £35 from a guy in Kent on eBay.

So proxy alignment is failing on the airbag ECU? Therein lies your problem then. Have you tried proxy alignment more than once? It doesn’t always work first time.

It may be worth putting the old one back in and seeing if a proxy alignment will work on it. That will rule out the speedo or the clock spring being the problem.

I believe i broken the old one trying to read the eeprom, finally got it connected to xprog, but reads and checks ok but only FFs and yyys so whether no crash data or broken, i tried anyway before and no luck, no connection at all with airbag ecu, my only other thought its the front crash sensor, when i plugged the new ecu it came as error and replaced it, but couldnt get the same so fitted the one i found, not expensive on fiat, but have to wait a week for it, and needed to MOt asap, fault gone , so expect it was a good fit but...

typecastboy said:

Have you still got the old airbag ecu? It would be better to have the crash data wiped and use the same one. It costs £35 from a guy in Kent on eBay.

So proxy alignment is failing on the airbag ECU? Therein lies your problem then. Have you tried proxy alignment more than once? It doesn’t always work first time.

It may be worth putting the old one back in and seeing if a proxy alignment will work on it. That will rule out the speedo or the clock spring being the problem.

Click to expand...

My fault

typecastboy said:

Have you still got the old airbag ecu? It would be better to have the crash data wiped and use the same one. It costs £35 from a guy in Kent on eBay.

So proxy alignment is failing on the airbag ECU? Therein lies your problem then. Have you tried proxy alignment more than once? It doesn’t always work first time.

It may be worth putting the old one back in and seeing if a proxy alignment will work on it. That will rule out the speedo or the clock spring being the problem.

Click to expand...

Yeah blue and me works original ecu was 51782985 new one (perfectly read on mmes but eol fail, request out of range error)51848079
Tried pa lots of times with no luck

Celefiat said:

The airbag lights do not come on at all. No when you switch ignition too.
Howeever.

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Has someone pulled the airbag light out of the display, hiding the fact there's a fault?

John202020 said:

Has someone pulled the airbag light out of the display, hiding the fact there's a fault?

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Never know, maybe, but its no faults in the module, just not alligning

John202020 said:

Has someone pulled the airbag light out of the display, hiding the fact there's a fault?

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Just a thought, if someone removed the dash lights to hide the fault, that may interfere with the allign? Also, dashboards are affordable, but it will change the mileage if i replace it with a breakers one?

Celefiat said:

but it will change the mileage if i replace it with a breakers one?

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You can edit the mileage using MES, but only upwards; so you would need to find one from a breakers with lower miles than your existing one.

jrkitching said:

You can edit the mileage using MES, but only upwards; so you would need to find one from a breakers with lower miles than your existing one.

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But if its higher it will be permanently changed? Just to test, i have a scrapyard round the corner and for sure they have one.
Any other thoughts about the ecu?

I tried to activate them in the actuator menu. It says activating but nothing happens, wondering if more than removing the leds they removed the connection with the airbag some way.
Anyone thinks that removing the leds will interfere with the connection for proxy align?
If there is a crash stored it will show a fault or just not connect?