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ABS light after MOT

Posted: Mon Oct 04, 2021 9:42 am
by Millses
I collected my car from its MOT last week, I noticed it now has an ABS light on and warning light. It had a new tyre fitted plus "Nearside Drive shaft joint constant velocity boot split or insecure, no longer prevents the ingress of dirt (6.1.7 (g) (ii)) Offside Front Anti-roll bar ball joint excessively worn (5.3.4 (a) (i))

Could it be the repair of these caused this light to come on, or is this a totally separate issue? My manual makes out its not a serious problem and that ABS can even be turned off, but online advice says to get it towed and don't drive it!

It's booked in for Friday at the same place. Do I drive it or ignore and leave it on the drive? Thanks.

Re: ABS light after MOT

Posted: Mon Oct 04, 2021 10:03 am
by calnorth
If the ABS system is faulty it should revert to FAILSAFE. Meaning it behaves as a system without the ABS function..so brakes should be ok.

Check the Brake Fluid level and ensure the brake pedal is hard to press...meaning the system is ok. Check the brakes work ok..of course.

Its possible they have dislodged/damaged an ABS sensor connector when removing the wheels etc.

Not sure if Tyre Pressure sensors (if fitted) may disable ABS...wrong wheel/tyre diameter will.

Re: ABS light after MOT

Posted: Tue Oct 05, 2021 9:43 am
by MrSweetE90
I'd also be a little strict with the fact this ABS issue occurred only after the MOT, don't pay for there wrong doings! Where the tyres replaced as calnorth is also leading to? If they where replaced or for what ever reason the tyre pressure are now different the rotations of the wheel will be different so the ABS sensor may think one wheel rotates quicker/slower to the other wheel so it may be a good idea to also double check pressures are equal.

Re: ABS light after MOT

Posted: Wed Oct 06, 2021 8:13 am
by calnorth
I've experienced a garage fit 2 under size rear tyres to my BMW. Meaning overall wheel/tyre diameter was smaller. My ABS flagged up at about 25mph.

The idiots still flourish I suspect...me too for not noticing.

Re: ABS light after MOT

Posted: Mon Oct 11, 2021 8:07 pm
by Millses
Thanks for the advice, a little update, the mechanic said it was the brake fluid needed topping up, he did it and the lights went off... for a while, I had to do a motorway journey today and the two orange 'ABS off' lights came on again - with the red warning light coming on intermittently - more off than on.

Anyway, as I drove on the drive I noticed fluid on the ground in the headlights where the car had been stood. So it must have a leak somewhere.

Re: ABS light after MOT

Posted: Tue Oct 12, 2021 7:41 am
by calnorth
Millses wrote: Mon Oct 11, 2021 8:07 pm Thanks for the advice, a little update, the mechanic said it was the brake fluid needed topping up, he did it and the lights went off... for a while, I had to do a motorway journey today and the two orange 'ABS off' lights came on again - with the red warning light coming on intermittently - more off than on.

Anyway, as I drove on the drive I noticed fluid on the ground in the headlights where the car had been stood. So it must have a leak somewhere.

...

You should see it in the engine compartment somewhere or under the car...pipes.

Re: ABS light after MOT

Posted: Tue Oct 12, 2021 12:08 pm
by Millses
it's going in a different garage tomorrow, will see what they say and update, thank you .

Re: ABS light after MOT

Posted: Tue Oct 12, 2021 10:26 pm
by MrSweetE90
calnorth wrote: Wed Oct 06, 2021 8:13 am I've experienced a garage fit 2 under size rear tyres to my BMW. Meaning overall wheel/tyre diameter was smaller. My ABS flagged up at about 25mph.

The idiots still flourish I suspect...me too for not noticing.
The thing is, we put faith into garages and not many in my experience have been reputable, from mistakes to plain cons you have to have your wits about you and your not always in that frame of mind. Unfornatelly it seems the same in this instance, it's been to a garage came back with a fault and they're taking no responsibility by the sounds of it. Hopefully the OP gets it sorted, especially if it is brake fluid leaking!

Also OP be extremely careful if you notice your brake fluid go down again, trapped air and brake fluid absorbs moisture are some of the things you may get if there's a leak somewhere so be very proactive

Re: ABS light after MOT

Posted: Wed Oct 13, 2021 10:47 am
by Millses
Thanks for all the advice, it's been helpful.

This garage have said the brake pads had shifted which could have been a rusty hook/bracket which has been replaced. They charged £39 which was £2.50 for the part the rest Labour and VAT. I am still thinking could the MOT have caused it, or just general wear and tear or going through the car wash frequently which does the underside too, I will never know.

Re: ABS light after MOT

Posted: Wed Oct 13, 2021 11:15 am
by calnorth
Millses wrote: Wed Oct 13, 2021 10:47 am Thanks for all the advice, it's been helpful.

This garage have said the brake pads had shifted which could have been a rusty hook/bracket which has been replaced. They charged £39 which was £2.50 for the part the rest Labour and VAT. I am still thinking could the MOT have caused it, or just general wear and tear or going through the car wash frequently which does the underside too, I will never know.
...

Front or Rear?