Shuddering brakes when coming to stop

[Mustachipleb]

Update (09/12/2024): I'm bringing in the car at the garage today, I'll update once I know more.

Hi, recent new user of a 2021 ID.3 with a weird braking issue here.

When braking to a halt, the car sometimes for the last meter or so of braking suddenly starts shuddering; with brakes applying much more forcefully than is normal.
This started less than a week after I began driving the car a couple weeks ago. It's a company car and had been standing still for maybe a month or 2 before.

It's a difficult issue to describe, plus it's seemingly very random in when it does occur. There seems to be a semi-pattern to it.
Where one day it will be fine and I don't notice anything weird, the next day (or longer) it will shudder.
See the videos below for example. They're mild examples but it was the only time I've been able to capture it on video.




Note that in the videos, I kept the same pressure on my braking pedal until after the shuddering begins.

It only happens at those last moments before coming to a standstill, and at the worst moments (usually when quickly braking from higher speeds), it will feel like the motor is either applying some uneven torque, or one of the brakes is locked up for less than half a second when I want to start moving again.

I've already consulted a mechanic and will be dropping off the car in a couple weeks, but they've said they currently do not have an idea what could be the issue. So, I figured I'd post it here to see if any of you have had a similar issues or seen something similar happen.

Disabling front assist/auto hold also does not affect the issue. It also happens independently of whether I drive on B or D mode. The best way to minimise the impact I've found is to drive on B mode and let the engine do most of the braking, and very lightly applying brakes over a longer distance to then come to a halt. This doesn't always fully eliminate it, but the effects if I'm going 2-4kmph are much less noticeable.

There is one fault code on the brakes in OBD data, but I have no idea whether it's at all related:

Code: Select all

System description: ESC-ZF_EBC470
Software number: 1EA614517AR
Software version: 0524
Hardware number: 1EA614517
Hardware version: H15
Serial number: Redacted
ODX name: EV_Brake1ZFESCEPBMEB
ODX version: 013164
Long coding: 09954A84153F903D523DA8E711E011A648294916443111492888886512949268228C889214CECBBCFD0073D33DBF00

Trouble codes:
U14D600 - Electronic central electrics control module Received malfunction value
Intermittent

Could this be a sensor malfunction? Maybe a mechanical issue with the brakes?

Any and all help appreciated

[sidehaas]

Whether you are using B or D, the vast majority of your braking is done with regen. It does sound to me like it's probably a mechanical brake issue if it is happening just before you come to a stop, but I'm no expert. You can test this theory by briefly flicking the car to N and braking when you have a clear road (it then uses the mechanical brakes immediately so you should see your judder more quickly).
Could it be warped front discs? That's an easy one for your mechanic to check anyway. I remember a user of these forums getting warped front discs back in 2022ish and having a fight with VW over whether they would pay. I have also heard of an ID 3 that had drum brakes sticking due to some sort of water ingress but I don't know what the symptoms of that were.

[Boattrainman]

Almost certainly a mechanical issue with the brakes.

Could be as simple as contamination between the brake pad and disc, oil or leaking brake fluid, so failure of pad to bite the disc.

Could be worn pads, or warped discs (a bit unlikely), or the pads are not evenly mating with the discs due to moisture in the system, the twin pistons may not be mating correctly with the back of the pad.

Or a loose bolt on one of the calipers (unlikely), or problem with the master cylinder (also unlikely).

I don't know the sensor set up for the ID3 brakes, so can't comment on that, I reckon your mech should have it diagnosed fairly quickly and its prob new pads and a brake bleed, hopefully nothing worse.

Rob

[libks]

Watching the videos, it simply seems like the ABS kicking in... or does it also happen if you brake more gently?

[Mustachipleb]

Watching the videos, it simply seems like the ABS kicking in... or does it also happen if you brake more gently?

Yes, this tends to happen when queuing/crawling in traffic as well, at as low as 5kmph. It's definitely not normal behaviour.

[Mustachipleb]

Whether you are using B or D, the vast majority of your braking is done with regen. It does sound to me like it's probably a mechanical brake issue if it is happening just before you come to a stop, but I'm no expert. You can test this theory by briefly flicking the car to N and braking when you have a clear road (it then uses the mechanical brakes immediately so you should see your judder more quickly).
Could it be warped front discs? That's an easy one for your mechanic to check anyway. I remember a user of these forums getting warped front discs back in 2022ish and having a fight with VW over whether they would pay. I have also heard of an ID 3 that had drum brakes sticking due to some sort of water ingress but I don't know what the symptoms of that were.

Tried to emulate this, but unfortunately the issue has been occurring relatively little the past few days, and I couldn't get it to trigger on the moment where I was safely able to test this. I'm bringing it in today, I'll update the post/add another reaction once I get feedback from the mechanic.

Thanks for the help!

[Mustachipleb]

Almost certainly a mechanical issue with the brakes.

Could be as simple as contamination between the brake pad and disc, oil or leaking brake fluid, so failure of pad to bite the disc.

Could be worn pads, or warped discs (a bit unlikely), or the pads are not evenly mating with the discs due to moisture in the system, the twin pistons may not be mating correctly with the back of the pad.

Or a loose bolt on one of the calipers (unlikely), or problem with the master cylinder (also unlikely).

I don't know the sensor set up for the ID3 brakes, so can't comment on that, I reckon your mech should have it diagnosed fairly quickly and its prob new pads and a brake bleed, hopefully nothing worse.

Rob

Thanks for the reassurance! I'm bringing it in today, and I suppose we'll find out soon what the culprit actually is

[Laurie71]

Last winter my car developed an audible/felt thud-thud-thud sensation whenever the friction brakes were applied followed by grabbing when coming to a halt.

I was convinced there was a problem but dealership took a look and said nope, just surface corrosion on the pads.

Sure enough after some harsh braking on quiet roads the problem went away.

[Midgex]

Rusty discs, isn't it?