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9N3 2006 TDI brakes coming on (front right/rear left)
Had a new master cylinder installed and notices (eventually) that pedal was often high and firm.
This eventually manifests itself in brakes applying themselves randomly but rarely. (6 months 20 incidents)
The trigger seems to be big down hills.
the solution seems to be to pull over and apply pressure to the brake pedal, which is high and firm, the pedal eventually falls and pressure is dissipated. Brakes then release.
Car has been to VW service centre - outcome - no fault found
Car has been to local garage - same outcome - no fault - including caliper check - excessive wear noted FRH/RLH disc and pads.
No abs or ESP incidents logged.

Help needed and appreciated - great car other than this problem which no one seems to be able to diagnose or fix.

If no one comes up with useful info on this forum, try joining the Skoda one ( www.briskoda.net ) and open a similar thread on the Fabia Mk1 section, you will probably find some "takers" there as they seem to like problems!

Brake servo could be faulty

alexperkins wrote: Fri Oct 13, 2017 12:13 pm Brake servo could be faulty

True, but it only seems to be a problem with one of the two brake/fluid systems.

Definitely not a servo issue. The big clue is the "front right and rear left" - diagonal, which how the two brake hydraulic circuits are split.

First check has to be the brake pipes from the master cylinder to the ABS unit - check they have not been crushed. If they are ok, then it will be a new master cylinder.