Mk1 (2003) Focus Airbag light - B2855 code / 4-2 flashing

[ctid]

Hi, I'm hoping you guys might be able to help. My girlfriend has a 2003 model Mk1 Focus. The airbag light is on and is flashing the 4-2 code. I read the codes with Ford VCM and got the following:

B2227 Front crash sensor/communication support
B1318 Battery voltage: Too low
B2855 Rear impact sensor: Short circuit to positive or short circuit to negative

After replacing the front crash sensor and clearing the fault codes, the light is still on and I'm left with this code:

B2855 Rear impact sensor: Short circuit to positive or short circuit to negative

I've done a few searches and can't find much info on this. Does the Mk1 Focus have a rear impact sensor, or could this be an issue with one of the front seatbelt pretensioners? I've checked the orange plugs under the seat and they're all connected ok. I can't see any damage to the wiring either.

The MOT is due and obviously it won't pass with the airbag light illuminated after the MOT regs changed, so any help would be much appreciated here.

Thanks

Edited by ctid on Wednesday 11th September 20:54