Technical Airbag ECU B0100-49 Fault code Error inside the control unit

[martinthomas747]

Hi All,

Newbie to the forum looking for some help and hopefully I can offer some in return in the future, got a weird fault on my 2008 fiat 500 1.2.
The airbag light came on and plugged in with Autel and MES and i get this fault: Airbag ECU B0100-49 Fault code Error inside the control unit.

After alot of head scratching I sent it to crash data for a reset as apparently it can get locked up software wise with this fault, it came back plugged in and all good for a couple of days and then randomly its come back.

I didn't know if anyone else has had issues with this code or knew any common faults with this. Car has had a new battery and earth strapped cleaned. No other faults on the car.
Ive got a paid copy of MES so can use features in that if thats any help.

Thanks in advance,

 

[steveras57]

Hi sorry to here of your problem!
I can tell you of the similar experience a work buddy had with there car (not a 500 but a 1.2 panda so pretty much the same!).

To be totally honest i dont remember if it was exactly the same fault code but the symptoms sound the same in as much that the message "internal electronic failure" is there!.

Like yourself she ( or more accurately her husband!) sent the unit away to be checked and it came back" repaired!" they refitted it and all was well for around a month then like yourself the fault code re-appeared!. having spent good money to no avail rather than try again to mend the fault they went down the route of purchasing a used replacement ECU!.

I think they said its important to find a unit with the same part number as the original and that there are some procedures to perform via multi ecu scan once fitted!.

I seem to remember her saying that the firm they sourced the replacement ECU from told them that its not unknown for the chip that controls the crash data records and reset function to fail completely and once this happens then the unit is in useless as its not cost effective to rebuild it!.

I would suggest contacting a good used spares supplier ( such as club 500 Italia) to see if they have any replacement ECU,S in stock and maybe they could offer you some further advice!.
hope this helps in some way! and good luck sorting it out!

 

[martinthomas747]

Just to update this thread,

The part number of my ECU apparently was plagued with faults, after alot of research I found I could use a different number ECU, still metal cased though and after a proxi alignment on MES all is fine.