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Airbag MIL - code RCM B0090:81-AF

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643 views 2 replies 2 participants last post by  Hoon Dog  
H
#1 ·
Hoping someone with some FORScan experience can maybe help here. I had my battery out for a few days recently when doing some other work under the car. When I put it back in, I noticed the Airbag light would stay on now. I messaged my tuner to see if there was any chance this was related to a VIN issue or something, but we discussed how I was also having a P08B2 code for likely low battery voltage (OEM battery from 2017).

I've since installed a new OEM battery, as well as checked both front crash sensors. One sensor was a bit loose, but even after disconnecting both and ensuring good contacts, I am still getting the light/error. Key areas I've worked on, in case it helps:
  • Downpipe replacement, and all the stuff that goes with that
  • Bumper/front clip off many times
  • Installing flex fuel system, including running wiring through the firewall (no cuts to the harness) and from the passenger footwell to the OBD connection, through the dash and under the steering wheel

I hooked up FORScan today and got the detailed code listed in the title. Specifically:

Code: B0090 - Left Frontal Restraints Sensor

Additional Fault Symptom ( :81):
- Invalid Serial Data Received

Status (-AF):
  • DTC Present at Time of Request
  • Malfunction Indicator Lamp is On for this DTC

Module: Restraint Control Module

Can anyone confirm if this would mean DRIVER side as left, or PASSENGER side? Has anyone else had this issue/code before, and how did you resolve it? Did it end up being a bad sensor that needed replaced, or a bad ground, or anything like that?
 
#2 ·
Hoon Dog said:
Can anyone confirm if this would mean DRIVER side as left, or PASSENGER side?
Click to expand...
You know, here on the forum we have some guys from Australia and UK, whose steering wheel is installed in place of glovebox. So their vision of DRIVER/PASSENGER side might not match yours :D
Unless you are one of those, then yes, LH means driver side of the car.
Image


AFAIK, our cars are equipped with 2 identical front collision sensors (and 'regular' focus have only 1 sensor in the front). So if I were you, I'd start with swapping them and seeing what happens.
 
H
#3 ·
Thanks! That's exactly why I asked haha (that, and I've seen some directional rotors labeled "Left" but meaning passenger side on LHD), so I figured I'd double check.

Swapping is a smart idea, I'll see if that moves the code to the right side. If not, which is my fear, is there any other sensor or connection location (like under the dash or wheel) that might also flag?
 
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