Airbag Fault 3

[Aviator912]

My car was at the body shop and it came back with the airbag light on..

I have bought a Durametric and it comes up with 3 faults, Fault 3 being the first, saying low voltage or something to that effect.

I assume this means the input voltage to the unit is low?? if so how do I check it, is there a fuse to test first?

The Durametric doesn't appear to be resetting the unit anyway.

Does the light being on result in a MOT fail?

Many thanks