Airbag Fault Code

[Cumbrian]

I have a permanent airbag light showing and my Red OBD is showing Fault Code B0079 "Incorrect LF/Driver SIS Installed".  I assume LF means Left Front and SIS means "Side Impact Sensor".  I also assume the word "Driver" is only applicable to LHD cars as Code B0081 refers to "Incorrect RF/Passenger SIS Installed".  The fault light has only recently appeared so the SIS would be the original correct fit.
I have disconnected and spray cleaned sensors under the seat, on the SIS (both sides), the drivers seat belt pretensioner and both the seat belt reel pretensioners and replaced the left side SIS (part number 9810452480) with a new one with the same part number. There has been no change to the airbag light or Fault Code. I have cleared the codes but B0079 comes back immediately.

I am now puzzled as to what to do next.

Has anyone else seen Fault B0079??

[Cumbrian]

The airbag Fault Codes were getting worse; seven airbag faults now. Perhaps the ECU was failing? I tried a new battery (the old one was showing signs of low voltage) but no change.
I was resigned to having to book it in to let the dealer connect his code reader and tell me the worst.
   

I was also having problems with the reversing camera which I fitted a few months ago. The display was flickering so I switched on the ignition and started wiggling wires looking for the suspected poor connection. I also noted when wiggling wires behind the drivers interior light that the dashboard airbag warning light was also flickering. The only airbag item in that area is the airbag deactivation light and I noticed on close examination that it’s plug was not pushed right in so I cleaned it and pushed it in. The airbag warning light on the dashboard went out and five days later I have not seen the airbag warning light or heard the dreaded warning ding.


Eureka! A check with the Red OBD showed no airbag codes.


So the deactivation light and seat belt electronics in the overhead console must be part of the airbag logic or circuitry which I had not expected.


And if anyone is looking for airbag faults they need to include the overhead console in their circuit checks.