Golf 5 2.0 TDI 4-Motion rear brake caliper

Hello fellow enthusiasts,

I'm having a problem with my Golf 5 where the rear left brake gets hot after driving for longer distances.
First, the brake caliper was replaced because the cylinder boot had a tear.
However, after the change, the problem was not resolved.
Therefore, the handbrake cables were replaced, and a basic adjustment was performed.
Wheel bearing replaced.
Everything was unsuccessful.
Now I've replaced the brake caliper again, and the problem still persists.
The error memory is empty.

Do you have any other advice for me?
Brake force distribution? Is the drain clogged or something?


Best regards,

Hi,
Sometimes, the brake hoses can corrode from the inside and become clogged.
It could also be the master cylinder.

Best regards,

Hello,

I'm just going to replace the brake hoses myself. There's nothing visible as far as I can see.
Also, I just had the vehicle inspection, and the braking performance is excellent.
The car brakes normally, and the pedal doesn't feel soft, so how can I check the master cylinder?
It only makes sense to me that the brake fluid can't flow back if it's due to the lines or the cylinder. Or maybe the ESP/ABS is malfunctioning. Can I check this with VCDS? So far, the control unit has always kicked me out whenever I've tried to create a log to check if the wheel speed is the same for all wheels.

Does anyone have any ideas?

SG

Is the ESP (Electronic Stability Program) activating for some reason?

You have a 4motion vehicle. It has a rudimentary differential lock function achieved through asymmetric brake intervention using EDS or XDS. This could be a software issue or a problem with the (ABS wheel speed) sensor. Therefore, I would suggest looking there first before making any further modifications to the brake hardware.

Sincerely,
Christian

Rudi was faster.

servusssss wrote:

So far, the control unit has always kicked me out whenever I tried to create a log to see if the speed was the same at all wheels.

Yes, unfortunately, it's designed for safety reasons so that the ABS/ESP control unit cuts off communication above 30 km/h.

I would try removing the fuse for the ABS/ESP system and then driving, so you can be sure whether the problem is caused by a mechanical or electrical issue.

Hello everyone,

After a trip without fuses (4 pieces), the brake continues to overheat.
Okay, I'm going to replace the brake hose now, because otherwise, the only thing left would be the master cylinder.
Do you have any other ideas?

SG

Hi!
Just pretend you're changing the brake fluid.
Only on the affected brake caliper.
You'll notice it right away if the hose is clogged. If nothing, or only very little, comes out.

I've personally seen 2 or 3 brake hoses that were either clogged or swollen in my life, but those were very old vehicles.
I don't believe this.

Sure, here is the translation of the text from German to English:

"Another question:"
Has any repair work ever been done in the area of the master cylinder/brake booster/brake pedal?

I'm not sure if this is the right way to do it, but in some older cars, you had to adjust the clearance between the pedal linkage and the master cylinder.
If you miss the optimal timing or set the pressure too low, the brake can seize or overheat.

Hi,

I don't think the brake hose is the problem either; it's new. I had forgotten because the dealership took care of it.
I would have noticed if it had been more difficult to bleed the brakes, especially since I just replaced the brake caliper.
"Nothing has ever been done to the master cylinder/brake booster/pedal or whatever."
Can I check anything else? I'm not really into randomly swapping parts.

"Additionally, I'm no longer able to establish a diagnostic connection with the car. It appears that the CAN bus is not functioning." It only became apparent after the security measure was implemented.
Does anyone know which fuse this is? I didn't see anything in the manual, or maybe I'm just not looking closely enough.

Thank you very much for your efforts!

SG

Hello,

Have you taken a closer look at the pivot bolts in the seat clamp?

If they are bent or crooked, the brakes can also overheat.

bloesch wrote:

Hello, Have you taken a closer look at the pivot bolts in the seat clamp? If they are bent/crooked, the brake can also overheat...

If that is the case, it is clearly visible in the wear pattern of the brake disc compared to the other side.

Hello everyone,

I have a quick update.

Here's what I've done with the brakes:
If the brake hose, brake master cylinder, or a check valve are not functioning correctly, meaning the brake fluid is not flowing back properly, then the brake should release when you open the bleed screw.
Okay, put the tools in the trunk and drive until the brakes are hot, then take the wheel off and loosen the bolt. Result: No change.
Therefore, I would rule that out.

That's why I took the entire brake assembly apart again. What's noticeable is that one guide pin in the brake caliper bracket has significantly more play than the other, about 2-3mm of feeler. Otherwise, the bolts move freely and there is no visible deformation.
Okay, I'm going to replace the brake caliper bracket now, and otherwise, I'm out of ideas.

I'm looking forward to hearing your opinions on this.

SG

If the guide pins have excessive play, the brake can become misaligned. If the pins seize, the brake can also become stuck. Applying MoS2 paste to the guide pin has prevented this issue for me for the past 15 years (?).

In addition, the brake pads must be able to move freely within their guides and must not be stuck. Therefore, remove any rust or corrosion present during brake pad replacement. If necessary, use new guide plates for the brake pads, or lubricate their guides with copper grease. Handle ceramic paste.

If the rubber seal on the brake caliper piston is damaged when retracting the brake pads, this can lead to a seized brake due to corrosion and/or the ingress of dirt over time.

Best regards, Rainer.

Hello everyone,

Unfortunately, I'm having the same problem with the brakes again, this time on the rear left side of the car.
It was exchanged/checked.
- Brake disc and pads.
- Brake caliper
- Brake caliper bracket
- Brake cable detached.
- Fuses for ESP/ABS/All-wheel drive removed.

Unfortunately, the brakes are still getting hot.

Does anyone have any tips or documentation for me regarding this braking system?
Wiring diagram/components, etc.?

I'm looking forward to hearing your ideas.

Best regards,

Christian