Technical Could the missing front bumper cause an airbag light?

[RobHowdle]

A shot in the dark but I thought I'd ask. I've currently got the front bumper off my car (2018 Estate) but I've noticed I have a check airbag light. I also had the left wing off for repainting and when I unclipped the indicator side light, I got a warning light saying to check it. When I put the wing back on and the light back into it's position, the light disappeared. Before I take it to an electrics place, does anybody think the car can tell the bumper is not attached and is then causing the light to come on? Naturally I'd have stuck it back on to check but I'm waiting for a few more parts and knowing my luck I wont be able to get it back off again if I put it on now

 

[chris3234]

Iif there some sort of impact/collision sensor in the front bumpers it's possible but I think think there's anything like that there?

 

[RobHowdle]

There is an anti collision sensor but that shouldn't cause this issue as it's not linked to the airbag system, it just tells you that the car is too close to another car and possibly applies the brakes. There is a crash sensor which I replaced but that is located under the drivers seatbelt, not in the bumper. Other than that I can't see any other sensors anywhere

 

[chris3234]

Agree the auto brake thingy shouldn't cause an airbag fault

There is an anti collision sensor but that shouldn't cause this issue as it's not linked to the airbag system, it just tells you that the car is too close to another car and possibly applies the brakes. There is a crash sensor which I replaced but that is located under the drivers seatbelt, not in the bumper. Other than that I can't see any other sensors anywhere

 

[RobHowdle]

Agree the auto brake thingy shouldn't cause an airbag fault

SG Petch tried to con me out of 3K+ for this. They said the anti-collision is an instant MOT failure and then they wouldn't replace the sensor until I had bodywork done (I'd only had a tiny little bump at this point) then they said it might fix the issue but if not they'll get a new sensor but the last time they ordered a sensor like this, the number "began with a 4"

 

[AndyRKett]

Agree the auto brake thingy shouldn't cause an airbag fault

Disagree, everything is on the Canbus system of the car. information may be passed to the airbag module in some cars which are able to recognize when a crash is not avoidable and deploy the airbags prior to impact. Therefore an anti-collision sensor not being available on the canbus system is highly likely to have some impact on things like the airbags not working or being deactivated.

There is a crash sensor which I replaced but that is located under the drivers seatbelt, not in the bumper. Other than that I can't see any other sensors anywhere

If you have been swapping things about without removing the battery then it is just as likely this has caused the airbag light.

The question is what is the reason for the bumper being off, the wing being repainted and the crash sensor being replaced ? if the car has had an accident then the airbag system will know and the airbag module may need replacement.

The only way to know why the light is on is to plug it in and see what fault code is recorded. You'll probably need to plug it in to reset the airbag light anyway.

 

[RobHowdle]

So after the first bump, the anti collision sensor (brake control light) came on and the feature of auto applying the brakes stopped working however this didn't cause any airbag light. After the second crash the light has come on. I'm lead to believe that the issue is somewhere on the car itself as I have a 2017 model which I have done some testing with and there is no issue there. The errors that come up are to do with the drivers/ passenger side tensioners/ pretensioners, when I unplugged the drivers seat in the 2017 model, I got the same error but when I plugged it back in the error went away. I even swapped the seats from the two cars so the one from the crash was in the working one, there was no errors either. Even tried swapping the crash sensor and that still didn't work. I haven't replaced the airbag module thought.

The reason the bumper is off is because I've had to replace it entirely and then repaint it etc, same with the wing. They had to come off the car to get repaired and repainted. I've had a mechanic in who told me the errors on the system but I can't seem to clear them myself so he has cleared the other errors which are now working fine but you may be right that the module needs replacing.