2010 E70 X5 3.0d - Parking Brake Fault

[Sm[]key]

Unlocked car this morning and a loud crunching noise came from rear driver side of car. Lasted for a few seconds.

Start ignition, fault lamp came on and the parking brake wouldn't disengage.

Cleared error codes, did pedal reset still no change.

Pulled the emergency release in boot and that released the parking brake.

Does anyone know if this is safe to drive now released?

I have a long journey to make tomorrow, will I have a problem?

[IanP]

Mine had the nasty habit of re-engaging even when it was off

[X5Sport]

You could try taking the fuse out? That’ll stop the actuator unit pulling the cables. The actuators had a poor reliability reputation early in the model’s history but I thought that had been overcome. Not seen a failure reported for years.

Do not be tempted to buy a knock off replacement as they often don’t work properly, don’t clear the fault, or just are rubbish. Refurbed OEM may be expensive (though still cheaper than buying from BMW who want about a grand for a new one).

There were repair kits around but I haven’t looked recently.

[Leslie]

if its released it should stay of until you try and operate it again id have thought but the danger is it isn't fully released on that side but park brake is separate from rear caliper on these like older bmws .

[Lobster Pot]

Mine went couple years ago drove it for ages until I finally took it to a chap in Southport who repairs them had a walk into town had fish and chips walked back and all repaired and working again think it was around £350 obviously cheaper if you send him the part and fit yourself there’s also another in Bradford who does the same

[marti]

If your hands on the actuator unit is really easy to do, you have to remove it to change the the rear pads and it only a matter of unpluging it and pluging a new one in.....disconnect battery first so you dont get any errors....

[Sm[]key]

I got one off eBay for £100.

Took me a number of hours on Sunday to changed out, replaced discs / pads / shoes too!

Fitting the emergency release in the boot is a two man job btw!

I`m yet to open up the old unit due to corroded bolts, will drill them out to see what had failed!?

[X5Sport]

Probably a plastic gear! Why manufacturers insist on plastic for ‘high load’ items I just don’t get

[Leslie]

Think the brushes in the motor wear out too and see motors for sale on ebay but no idea if they would be good or not .

[Sm[]key]

WhatsApp Image 2024-06-28 at 20.54.08_f1321bbd.jpg (184.11 KiB) Viewed 4582 times

Took apart old hand brake mechanism, plastic gears seem ok. Hear a loud grinding sound when it failed.....

[X5Sport]

As you say, the gears look OK. The second reduction gear is dirty, but that’s probably from the retaining spring. The teeth all look pretty good. Curious if there’s any backlash or wear that would allow any of the three gears to jump rather than engage?

Parking brake cables OK?

It’s only the motor left if those two are fine.

[Sm[]key]

Yeah cables ok, couldn't see any visible damage or play.

My conclusion was the motor failed....

[Leslie]

The motor maybe has some sort of coupling which has failed at a guess .

[libra007]

I had fun with this swapping this one and few tries, i gone and replace the cables that came with the kit but these were the problem had too much flexibility so the pressure sensor wouldnt work properly. both new from BMW and new brake shoes solved the issue. make sure you adjust the parking brake pads nearly tight. motors hardly fail its the pressure sensor, that with any old corroded cable or too much gap in parking brake pads that starts this issue and further damage it can do by pulling too much.

when it goes wrong better to avoid engaging it as it got stuck on me luckily on driveway had to cut it, emergency procedure didnt work.

[X5Sport]

Thanks for the update