Ok, for anyone interested: Fiat Airbag Error B0102-00 can probably be solved WITHOUT having to mess with the EEPROM or sending it to repair center.
When I first had this error, it was intermittent and I could clear it with my
multiecuscan.
Remark: to access the Airbag ECU and clear faults with
MultiEcuScan you need the yellow adapter or the multiplex version. Some cheap adaptors and applications can read the fault and even have a clear faults button, but that does not work. And then you think that the fault cannot be cleared... So make sure you have a working ODBII setup first!
In the beginning, the fault came back every couple of days and I kept clearing it every time. But after a while it came back faster and faster, and then suddenly the fault became "present" (or "permanent" as it is called in some apps) in stead of intermittent. This means that at the time of reading the grouding fault is present. A fault that is "present" cannot be cleared. In this state it makes absolutely no sense to send the ecu for repair. They will force clear the error, yes, and the light will be out. But since the root cause is still there it will come back, typically after a week or two.
Since this is a grounding error, I checked all the pins on the ecu for obvious problems or corrosion and I measured the connections with a multimeter. All seemed good. I also checked the yellow connector under both seats. They connect to the seatbelt sensor en the pretensioner. I could not identify any issue. After putting everything back, the error remained present.
I then unmounted the ECU, opened it and cleaned (with very light sanding) all the ground contacts on the PCB board. I also sanded the paint of the mounting pins to make sure the contact was good.
After mounting the unit back the error was till there and present....
I almost decided to give up and send the unit in for repair, but then I remembered reading somewhere that it can take a couple of drives before these units acknowledge that a fault is gone. It is not a corrupted EEPROM as they like you to believe. The EEPROM seems so store events and data with a sort of FIFO method and the algorithm make averages and continuous new measures. There is also a difference between the analysis at cold start (when the engine and power have been off for at least a couple of hours or so), driving and warm start situations.
So I decided to wait and see.
And what do you know.. THREE days later the fault became "intermittent" again. So it was no longer present, but the ecu still remembered it. I cleared it. The morning after that it came back "intermittent" again. I cleared it one more time and it never came back again. We are now well over 2.000 km, dozens of drives, and two weeks later.
I have a strong feeling that the other common fault (B0100 - power) can also be solved by taking away the root cause and then wait for the ECU to notice it.
