VolvoXC40 auto - Uneven braking

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Thu 21 Jul 2022 19:56
VolvoXC40 auto - Uneven braking - Stan Chaplin
Bought in late 2019 prior to the pandemic has kept our mileage low at 9000 so far. Very early on we experienced a hunting/ hopping feel when braking or coming to a full stop. Reported at each of the 2 services. Initially we were told that rust had built up on brake discs because of the low mileage and that this would disappear. We were told the next year that a software upgrade would fix it. It hasn’t. I suspect it’s something to do with the auto and possibly other things such as stop/ start. It would put me off buying another. Anyone with ideas? Thanks. Stan
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Thu 21 Jul 2022 20:45
VolvoXC40 auto - Uneven braking - elekie&a/c doctor
I think I’d be looking at warped brake discs here. Front / rear or both .
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Fri 22 Jul 2022 12:33
VolvoXC40 auto - Uneven braking - Crickleymal

Same here, warped discs would be my guess

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Fri 22 Jul 2022 22:40
VolvoXC40 auto - Uneven braking - mcb100
Is it a mild hybrid?
If so, I’d suggest it’s the regeneration process whilst slowing down giving varying levels of ‘assistance’ to the overall deceleration. More noticeable at lower speeds, it’ll alter how much pressure you have to apply to the brake pedal on the last few metres before coming to a stop.
It’s sometimes a little more difficult to come to a ‘chauffeur’s stop’.
If it’s not a hybrid, I’ve no idea.
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Sat 23 Jul 2022 00:11
VolvoXC40 auto - Uneven braking - focussed

I would suggest that the brakes - pads and pad carriers - need a proper service.

This involves making sure that the brake pads are free to move in the pad carriers and not jammed up with corrosion and dirt.

But the average dealer mechanic doesn't know or care how to do this, he just prefers to peer at his laptop and parrot to the customer what is says.

Software update - says it all!

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Sun 24 Jul 2022 02:23
VolvoXC40 auto - Uneven braking - edlithgow
Agree with above “start at the basics” suggestions, partly because the basics are the only bits I have experience of and more or less understand. Brakes are even now primarily mechanical devices

Moving forward into the zone of 20th century witchcraft when software upgrades first roam the earth, sounds a bit like what I’d expect from an ABS malfunction.
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Sun 24 Jul 2022 10:39
VolvoXC40 auto - Uneven braking - Andrew-T
Moving forward into the zone of 20th century witchcraft ....

Good grief, Ed, you really are behind the times :-)

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Mon 25 Jul 2022 23:50
VolvoXC40 auto - Uneven braking - focussed
Moving forward into the zone of 20th century witchcraft ....

Good grief, Ed, you really are behind the times :-)

It's of no use to use electronica to sort out problems if the mechanica is letting you down.

Mechanicals first - electronics next if necessary.

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Tue 26 Jul 2022 03:21
VolvoXC40 auto - Uneven braking - edlithgow
Moving forward into the zone of 20th century witchcraft ....

Good grief, Ed, you really are behind the times :-)

Thats the plan.

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