Afternoon all,

Just wanting to share a fault and fix for future reference.

My 2012 L320 had a park brake fault not long after cleaning the inside and outside. GapIID tool read U2002-1, switch general electrical failure.

This fault means the EPB does nothing when pressed, apart from display a warning on the dash. No screeching or grinding noises from the module.

Research says it's likely to be chafed wires by the module, or a faulty switch.

As I did not have access to a replacement switch to swap, but do have access to a ramp I had a look at the wiring by the module today, accessed by dropping the spare wheel. I was expecting to find some previous repairs where perhaps water had gotten in during the cleaning, but all the wiring was in good condition, still in the original loom.

This lead me to think it could be the switch, but before ordering a replacement I took the old one out for a quick look. The black trim to the front of the EPB switch just pops off, exposing two T15 (?) screws, remove those and the switch comes up, electrical connector on the bottom.

Nothing looked out of place, but gave it a thorough clean with contact cleaner, inside as much of the switch as possible without taking it apart.

Switch back in and the EPB now functions as expected, so must have been some debris that worked it's way in when cleaning the inside of the car.

So, in short; in my case this fault was not caused by damaged wiring or the module, but a dirty switch. Plenty of contact cleaner and it's good to go.