Thread: brake light switch

Re-connected battery yesterday and brake lights still on. Tried wipers and indicators without key in ignition and they didn't work. Drove home and filled up with diesel, lights stayed on throughout. Then got home and lights were off and seems back to normal. Haven't checked anything else since as now all working. What should I do now ? Just wait till happens again, or is there anything I should now be checking whilst all seems ok ? Thanks for all your help on this.

you can't do anything as long as the fault is not present... when it happens again follow the plan and we'll see...it seems it's an intermittent short circuit... what you can do though is to check for water ingress in the interior fusebox maybe you can see a sign cos water ingress there is quite common

Thanks, still all good again, took about two weeks since last happened, so will be back when the bug comes back !

Ok so started again yesterday. I took out the F25 fuse and the lights stayed on. Will do the full check list this evening and report back. I though I might add that a few weeks ago I had a reversing camera linked into the head unit, after-market add-on that I am not using as had replaced the head unit 6 months back. Finally decided that as I would never use it so I cut it off, have I been a fool and is it possible it could be something to do with this ?

i was kinda expecting that, i dont think that the reversing camera has something to do with that, i have a feeling that the lights will go out when you remove F14 in engine bay... if it's so we are closer to the answer

Ok removed f14 and still lights stayed on......where next ?

then the things are becoming complicated, just confirm you removed F14 engine bay
1. are you up to do some measurements with multimeter?
2. do you have RAVE? cos you'll need it for the connector views

you didnt tell me if you remove F25 and push the brake are the lamps still getting brigter or not...this is important

unplug the brake switch see what happens

EDIT...also if you know where the cruise controll pump is unplug that too

the brake circuit is getting a back feed from some other system and that's what we have to find, the easy way would be to get hold of a interior fusebox and swap it to rule it out cos it would save you from many measurements....it's a very odd fault and needs serious troubleshooting

Hi, yes can confirm removed F14 from the engine bay, and do not have RAVE, I do have the D2 workshop manual, willing to do whatever is needed, currently back catching the bus and train to work, which is no fun ! Will check tonight with other half tonight, can you point me in the direction where the cruise control pump is ? Will check that this evening and report back.