How to Release a Stuck Electronic Parking Brake ?

[MartinFa]

You're a star - many thanks. I had to print out the article you linked to for the service guys so they could back off the brake before taking the car away to be fixed! (Recon caliper - £250 + VAT). (Stupid, over-engineered, unreliable, unnecessary replacement for a perfectly good lever & cables).

[sturner205]

Vehicle: VW Passat 2.0 TDI (50,000)
Problem: Seized Rear Brake Calliper
Diagnosis: Following leaving the vehicle for a couple of days the handbrake on the vehicle seized on and the vehicle could therefore not be moved. Following a search of the internet I determined it was a common fault on the vehicle fitted with the electronic handbrake and decided that I would try and fix it myself. From observation of the rear caliper it appears that the housing to which the motor sits in becomes cracked and allows water to ingress into the housing itself allowing the motor to seize up over time. In order to get the caliper retracted and testing of the motor itself I did the following;

1. From observation of the motor unit a crack has appeared on the casing of the motor.
2. Remove the motor from the rear of the caliper by losing the 2 x T30 Torx Screws. These maybe be slightly hard to remove as they are thread locked into position
3. Remove the electrical connector to the Rear caliper motor
4. To release the caliper to allow the wheel to turn you must us a T45 Torx driver and turn either clockwise or anticlockwise depending on the side. (If it does not loosen with ease a new caliper may need to be purchased.
5. Corrosion builds up around the sealing face of the caliper and therefore needs to be cleaned prior to re-installing motor.
6. Remove the o-ring from around the caliper without damage
7. Remove all traces of corrosion and clean the O-ring groove. In order to clean the O-ring groove I used a piece of twisted copper wire to allow friction against the surface.
8. Apply silicon spray to o-ring and place around the rear of the caliper again
9. To test the Caliper motor apply 12Vdc to the motor itself. Reversing Polarity to see if the motor turns in both directions. At first through trial, the motor did not initially move but after a few attempts it freed up and operated in both directions. I sprayed some service sol around the motor mechanism after.
10. In order to ensure that the motor does not come loose from the caliper the bolts will have to be thread locked again
11. Fit the motor back onto the caliper, ensure that the spindle from the motor is located correctly within the keyed part of the caliper. Fit power connector back onto the motor. Once fitted back to the vehicle ensure that all cracks around the housing have been filled with high temperature black silicon. This will prevent water ingress into the motor unit.

I have done this as a temporary fix as it is costly to get two new calipers for the car. This appears to be a common problem and believe from looking at the motor on the new Passat that this will be a recurring problem for new owners of Passats. Bad design and product testing has not been carried out and for German engineering it is quite a disappointment. I have only had the car for a month and this is the first issue. Hopefully I will not see any more.

[Whippy53]

Just had the same problem on my 05 plate, my local friendly indy replaced it with a pattern part for £300 all in, so not to bad for one. Mind you that still leaves me with a potential £900 bill for the future. Silly silly design!

[tempster]

i was going to suggest to use the vcd and put it in transport mode, as that sometimes free's up the seizure.