V70: Wheels/Brakes Electronic parking brake would not release

[capt jack]

Evening All

Driving home from work this evening I pulled up in a queue of traffic and applied the electronic brake. (The car is a 2012 V70 D5 auto with 146,000 miles)

When I tried to pull away the brake would not release, and no amount of pushing and pulling on the release button made any difference.

So I switched the engine off and restarted the car. The brake immediately released 100% normally. I drove home (about 35 miles) without using the parking brake at all. I have operated the brake dozens of times with the car sat on the drive - and it's worked perfectly. I can hear both motors whirring quite happily, and the brakes are fully released.

So, my question is, can the car's computer throw an EPB wobbly that's cleared by a restart, or is there more trouble lurking? Could I possibly have inadvertently caused an issue in any way?

I ask because in my ownership the car has done some odd-computer-related things that have then gone away - the BLIS for example, that will suddenly stop working, to work OK when the car is restarted, the random headlamp adjustment warning light that came on once, and was immediately fine after a restart, the low battery warning that fixed itself - yep, after a restart! There's a pattern emerging here of odd glitches that resolve themselves after a restart! On the basis that the car is a computer on wheels, is it just the case that like a PC, a restart is sometimes the only fix?

When I tried to pull away with the brake jammed on I got the feeling that as the car "sat down" evenly, both rear brakes were equally stuck on.

Brand new Pagid rear discs and pads were fitted about 5,000 miles ago, and everything has worked perfectly since then.

Would taking it all apart and giving it all a good clean make any difference?

I guess for now the sensible thing is not to use the brake, but if anyone has any insight and advice it'd be most welcome.

Cheers

Jack

[Kev0607]

I'm sorry if this sounds daft, but its easy to do...

When you say you pushed and pulled the release button, did you have your foot on the brake whilst doing so? If you didn't, the EPB won't release. Its an easy mistake to make when there's a queue of traffic behind you!

[Kev0607]

Edit: Double post.

This forum is woefully slow at the moment. Its took several minutes to post the above message. When it did, it sent it twice!

[capt jack]

Thanks Kev. Yep, I reckon the forum is being decidedly slow just now!

I should have mentioned that I got various dashboard warnings about the parking brake at the same time as it stopped working.

Interestingly, both the handbook and the Volvo website say to try to operate the brake a few times, and call for assistance if it doesn't work after that. Which tends to suggest that the occasional malfunction would be regarded as normal.

The advice is to take the car to a Volvo workshop if the problem continues. Although quite how you'd get anywhere with brake firmly stuck on and the car immobile isn't made clear! I guess even the recovery people would struggle. How would you pull a car up onto a low-loader with the rear brakes resolutely stuck on?

I'll see how it goes today, and have a look at the rear brakes over the weekend.

Thanks


Jack

[apersson850]

First, if the electric motor is fully reversed and then mounted together with pads that aren't new, it may not engage in a single run. The distance to go could be too long, and in that case you may need to operate it a couple of times. That could be what the manual is referring to.

I'd recommend removing the motor from the caliper and inspect the drive train for rust. If it's mechanically fine then the brake controller may be the culprit. Occasionally they do fail. We haven't had any problem with our two cars with electric parking brakes. Combined use is 600000 km.

I hardly ever use the parking brake in traffic (it's a parking brake, after all), but if you do, it should release automatically just by pressing the accelerator pedal.

[Kev0607]

Originally Posted by capt jack

Thanks Kev. Yep, I reckon the forum is being decidedly slow just now!

I should have mentioned that I got various dashboard warnings about the parking brake at the same time as it stopped working.

Interestingly, both the handbook and the Volvo website say to try to operate the brake a few times, and call for assistance if it doesn't work after that. Which tends to suggest that the occasional malfunction would be regarded as normal.

The advice is to take the car to a Volvo workshop if the problem continues. Although quite how you'd get anywhere with brake firmly stuck on and the car immobile isn't made clear! I guess even the recovery people would struggle. How would you pull a car up onto a low-loader with the rear brakes resolutely stuck on?

I'll see how it goes today, and have a look at the rear brakes over the weekend.

Thanks


Jack

If the brake was stuck on and the car had to be recovered, its likely that the person recovering the vehicle would disconnect the EPB motor completely, which would allow the car to move freely.

There's two options when it comes to parking in traffic. When the car is in "D", you can put the handbrake on and it'll hold the car whilst its still in "D". So long as your seat belt is on, all you have to do is press the accelerator pedal and it automatically releases.

The other option is don't use it at all. Just put the car in "P" at a standstill. Although, I'd only recommend that on a level surface. You don't want to have the transmission in "P" on the top of a hill, as it puts stress on other components.

It sounds to me like its an electrical glitch. As warnings popped up on the dash, but it released after a restart... That, or the EPB motor is dirty.

[GrahamBrown1]

A fault in the park brake module will then cause the park brake to be inoperable until a restart which has subsequently cleared the fault. If the fault was still present it would still be inoperable. A code however will be stored.It can be down to daft things like only part pressing the switch or the module not receiving the correct signal. I’d just keep an eye on it but Vida will give you more of an idea if it does become more frequent.

When P3 cars first came out they had no end of trouble with park brake modules. Many were changed under warranty from what I remember.

[capt jack]

Well the car was fine all day - although I didn't use the handbrake at all. But when I got home this evening I put the parking brake on and now it's well and truly jammed. I'm pretty certain that it's the nearside that's stuck.

I took the wheel off and had a look, and tried to dismantle things, but it's just beyond my limited skills and tools. One of the two screws holding the motor came out, but the other is well and truly seized. Beyond this, I can see that the motor housing is cracked, so I wonder if moisture has entered and caused the motor to seize up?

Anyway, I can't move it, and so it's the AA who'll be here in the morning, and unless the AA can fix it, a recovery to Dyrdals in York. They are open tomorrow, although I doubt that they'll be able to fix it on the day.

Heigh-ho!

Jack

[GrahamBrown1]

Originally Posted by capt jack

Well the car was fine all day, but when I got home this evening I put the brake on and now it's well and truly jammed. I'm pretty certain that it's the nearside that's stuck.

I took the wheel off and had a look, and tried to dismantle things, but it's just beyond my limited skills and tools. I can see that the motor housing is cracked, so I wonder if moisture has entered and seized it?

Anyway, I can't move it, and so it's the AA and a recovery to Dyrdals in York. They are open tomorrow, although I doubt that they'll be able to fix it on the day.

Heigh-ho!

Jack

Oh that’s not good, very much a mechanical issue with that calliper then. Drydals are good, we get most of our Volvos from them. Always nice to deal with and I hear there service dept now has the master technician from ray chapmans with many years experience.

[capt jack]

Originally Posted by GrahamBrown1

Oh that’s not good, very much a mechanical issue with that calliper then. Drydals are good, we get most of our Volvos from them. Always nice to deal with and I hear there service dept now has the master technician from ray chapmans with many years experience.

Thanks Graham. Yes, been going to Dyrdals for 20+ years, and have bought several cars from them, including this V70 last year. Had known Paul all that time and was very sad about what happened to him.

They do indeed have an ex-Chapman's tech in charge now, so I know it'll all be fixed. I must admit, it's dented my belief in the car - so much technology and complication when really, a manual handbrake is just such a basic and simple thing.

Right now I'm of a mind to start looking for an older S60 or V70 - although I guess that those cars aren't entirely without their issues too.

Such is life!

Jack