[SwankPeRFection]

Doubt it. Sounds like parking brake components are defective.

[Matt417]

I have found that Pulling the connector does stop sound from happening, but won’t solve it . It seems the calipers and pistons in rear are all good . It’s the e brake motor that’s the problem, it’s over twisting itself and causing the piston to squeeze harder then it should (I think)
But this won’t solve the issue, the actuator needs to be adjusted somehow to push/twist less. This only happens when applying the brake, then after a couple seconds the actuator/autohold/hill assist or something kicks in a little more, or when auto-hold is on or if your just sitting in D holding the brake pedal. That’s the creaking sound.
I have no idea if an electrical actuator can be adjusted because other then that everything else is functioning fine

I’m considering manually twisting the piston back a little bit, like when someone replaces the rear pads is required to, to reset it to have less pressure for the autohold. But I doubt that’ll do it the actuator will probably just move more
Or another option to pull the fuse temporarily for the auto hold, but I have no idea where that fuse is. It’s not the parking brake one, should be separate I assume in the trunk fuse box but there’s no diagram for that one

[SwankPeRFection]

Don’t take this the wrong way, but stop fucking with it and take it in with all of your diag info on what you found and have dealer swap out the motor or caliper. The way the parking brake works is the inner twisting screw inside the piston is made like a corkscrew and twists in and out applying pressure to the pad to engage the rear caliper to function as a parking brake. When this happens, hydraulic pressure in the normal brake like system isn’t used for this function. The motor has a built in resistance gauge that once it reaches a certain pressure, it knows the pads are engaged on the disc and it stops. Your servo motor probably has issues doing this and keeps trying to push on the pads… quite possibly it may be stripped inside and that’s what the sound you’re hearing is. The system stops when it either detects that resistance or if it sees the motor not stopping after a while. Your passenger side works fine, your driver side does not. The system also does a “pad thickness check” when you come to a stop and usually when you turn the car off after several miles where it’ll engage this same screw and clamp down on the parking brake, meet the resistance of a full engage and then back itself back off just a little bit. This self adjustment is also why software is required to put the back brakes into service mode to change out the pads. All that does is it fully dials back this EPB screw inside the caliper so that you can push the piston back in and install thicker pads.

FYI, fucking around with manually dialing back the motors when changing back pads is usually a good way to cause issues like this where something gets broken. I’m not saying that’s what you did, I’m just warning you that if you’re going to do your own work, just buy a cable and software and do it right.

Also, since it probably is the motor or gearing in the EPB mechanism, turning that screw back in some won’t do anything. It’s made to go in and out like that. The problem is stripped gears in it or the circuit in it that detects the resistance when it meets the pads and tells it to stop turning.


Hope all that makes sense and helps you get an idea of what’s happening.

[Matt417]

I’m just trying to narrow it down as much as possible, wouldn’t kinda call it fucking with it. At this point a wheel was off and a connector was disconnected.. after a lot of searching for this issue it seems a bunch of g80s have it. I got messages of guys on here that went to the dealer and was told it was normal brake operating sounds, etc and hopefully will avoid the same outcome..
Yes the motor or resistance is mostly the problem, and I mentioned even I don’t think a motor can be turned back like that. As we as the piston being screwed back in will just go back to its previous position.
Just figured to have as much info as possible for a tech so it less time in the long run, didn’t mean to get you all riled up about it if I did.
But thanks for the additional advice

[SwankPeRFection]

Well, any dealer mechanic that says it’s normal, if one side does it and the other doesn’t, guess what? It’s not normal, one side is defective. If they argue against that troubleshooting, find another dealer and also call BMW USA and complain about that place.

You should be able to still hear (the motor part) on the passenger side still engage with hill assist on even if the driver side is unplugged. That’s pretty much all the proof you’d need if you run into a complete idiot mechanic or dealership.

Anyway, good luck. Also, I hope you didn’t take my previous message to be mean. It wasn’t meant like that. One last thing… if they’re really stupid and still don’t replace it with all the evidence you’ve given them, tell them you consider it a safety issue since it’s brakes and ask them if they’re saying they’ll assume all responsibility if something bad happens and you decide to sue them? See if they want to document that in writing on your work order/receipt or just simply file a warranty claim with BMW and get paid by them for all the work and parts and have no liability issues. Seems like an easy decision to make…

[lilmanvc15]

I am having the same issue I thought it was just me. But it’s definitely like a loud creaking noise. Maybe we are babying it to much? I haven’t been doing any harsh braking during my break in period.

[SwankPeRFection]

Originally Posted by lilmanvc15

I am having the same issue I thought it was just me. But it’s definitely like a loud creaking noise. Maybe we are babying it to much? I haven’t been doing any harsh braking during my break in period.

Well, you can do the same thing the OP did as a test and if it’s the same issue, then it’s the EPB motor(s). I sense a possible TSB coming out from BMW if this becomes the norm for some vehicles. Maybe they just got a bad batch of rear calipers and they got installed on a few vehicles being built.

[MasterM]

Originally Posted by lilmanvc15

I am having the same issue I thought it was just me. But it’s definitely like a loud creaking noise. Maybe we are babying it to much? I haven’t been doing any harsh braking during my break in period.

Year and model of yours?

[Krisp97]

Not sure if it's the same thing but sometimes I can hear a slight clunking sound when lightly depressing the brake pedal and coming to a stop and releasing the brake slightly.

Just normal behavior of the caliper barely contacting and allowing slight slipping and re-gripping of the rotor, making it sound like a clunking

[JDUNITNOW]

Originally Posted by Krisp97

Not sure if it's the same thing but sometimes I can hear a slight clunking sound when lightly depressing the brake pedal and coming to a stop and releasing the brake slightly.

Just normal behavior of the caliper barely contacting and allowing slight slipping and re-gripping of the rotor, making it sound like a clunking

Might be irrelevant, did you lower your car? I was getting clunking and squeaky noise from my rear and it was the HAS springs making the noise. Once I switched, the oise went away.

[Krisp97]

Originally Posted by JDUNITNOW

Might be irrelevant, did you lower your car? I was getting clunking and squeaky noise from my rear and it was the HAS springs making the noise. Once I switched, the oise went away.

Stock suspension for me, I have heard of many people lowering on certain springs like HAS and AST having these noises which seems to be common

[lilmanvc15]

Originally Posted by MasterM

Year and model of yours?

2024 bmw M3 Comp RWD
It stopped happening after the break in service

[SwankPeRFection]

Originally Posted by lilmanvc15

2024 bmw M3 Comp RWD
It stopped happening after the break in service

Look at your paperwork. Maybe they heard the noise while in service and fixed it under warranty. If they don’t need to charge the customer, they wouldn’t have needed to ask your permission, especially if something was definitely effective and wrong.

[edi221]

Just asking if anyone has any further update on how to solve the noise issue?

I mean some said its the e-brake, and some not sure.

[SwankPeRFection]

Originally Posted by edi221

Just asking if anyone has any further update on how to solve the noise issue?

I mean some said its the e-brake, and some not sure.

If it’s the same noise, why not pull the EPB connector and see. If the noise goes away, you’ll know right away and then you can plug it back in and take it to the dealer to fix it under warranty. It’s not that difficult to unplug that plug from the back caliper.

[edi221]

Originally Posted by SwankPeRFection

If it’s the same noise, why not pull the EPB connector and see. If the noise goes away, you’ll know right away and then you can plug it back in and take it to the dealer to fix it under warranty. It’s not that difficult to unplug that plug from the back caliper.

Thank you, I will check with my dealer real soon.