EPB - Why is it doing this?

[PerthDisco]

Hello Gurus and best for 2014.

Late last year around 100,000km I had a visit from the EPB Screaming Fairy with flashing warning lights and normal rigmarol.

I have followed the various EPB posts here and on Disco3 and never used the auto EPB function.

I was all set to do a manual release but tried again after turning on/off and it worked again to release. I put some tape over the lever as plan was to get it looked at next service. Habit being what it is I did once or twice accidentally pull the EPB on and it worked to release each time.

So last week I had it serviced and they did a full service, clean and readjustment of the park brake mechanism via removing the rear discs etc. Something like 2.5 hours of labour which seems fair enough. The indi mechanic reflected all the knowledge of the system's foibles I have read about and I was very comfortable.

Following this the EPB worked incredibly silently.

On the weekend I had cause to park on a very steep driveway. On setting the EPB you could hear the creak/groan as the park brake took the load of the vehicle once brake was released. On returning to car to leave the EPB jammed and all the warnings flashed up again. As before, thank goodness, it chose to work after turning on/off again.

Once back on flat ground it worked silently and smoothly.

The next day same again on a small incline where the EPB was not able to retract under the load. Again, it worked once key was turned on/off.

I have never had to do the manual release.

Can you help me pinpoint what part of the system / mechanism is on the fritz here so I can go back to the mechanic with some ideas. I have seen the Disco_Mikey story http://http://www.disco3.co.uk/forum/post1062451.html#1062451 (http://www.disco3.co.uk/forum/post1062451.html#1062451) on servicing the central EPB drive
module. I would desperately like to avoid a visit from Uncle Big Bill on this one.

Thanks

[Graeme]

Are you aware that the cables are initially tensioned then more tension applied if the wheels start to turn, eg if on a slope? Hopefully the adjustment needs a 2nd visit but from the sounds of it your mechanic will know the reason anyway.

[justinc]

very important is to centralise the shoes after adjustment if not then it is possible for them to bind when under duress from big loads ie holding a vehicle on a slope. this is done after the shoes are adjusted , read through this link/ pdf it is very informative.

http://www.disco3.co.uk/gallery/albums/userpics/11748/Bodsys_Brake_Bible_V1.4sml.pdf


jc

[PerthDisco]

Thanks. Have seen the good book previously. Was contemplating printing off for the workshop just in case.

[Graeme]

..read through this link/ pdf it is very informative. I retrieved V1.5 from somewhere. V1.5 summary...


Jan 2011 1.5 Removed Loctite Instruction on Torx50 screw when changing disks. Fitting ‘Sticky’ side of some OEM pads instructions

updated. Added EPB Adjuster direction information. Section
Link updated. Updated Remove Pads before Shim
instructions. Added a few more pointers.

[PerthDisco]

Latest advice today is that there is some component within the actuator that detects when the car is parked on a steep slope to apply additional pressure. This would indicate that the problem is related to the more expensive actuator part. I will be nursing it from now on as seems to work OK on flat surfaces (when you don't actually need the EPB).

[101RRS]

My EPB works fine but I do not use it in most circumstances as the auto park pawl is good enough. The exceptions are on steep hills and when parked with a heavy trailer hooked up.

My drive has a bit of slope and I do not need it there. I am careful though to let the weight of the car come onto the park pawl slowly and I have never had an issue disengageing it when driving off.

Garry

[PerthDisco]

I have been doing same for past month before service. It definitely does not feel good doing it on steep inclines. Agree with easing weight onto the pawl rather than bouncing.

Annoying problem to have.

[PerthDisco]

Update to this story. After asking for a second adjustment all good as gold again. Phew!

[Grappler]

Here is a link Ian Bodsworth gave me recently with the most upto date
ver 1.6a


http://www.disco3.co.uk/gallery/albums/userpics/11748/Bodsys_Brake_Bible_V1_6a_CompressPics.pdf