Brake lights constantly on

[Greigzy]

So, when the car is running, the brake light is constantly on. When the brake pedal is pressed, they light up a little more, but stay on.

When the car is turned off, the brakes lights go off, and if you press the brake light, they light up as they should.

I have replaced the brake light switch, which has made no difference.

Any suggestions with what to do now? Could it be a relay?

[mb]

Haven't got my Mk5 anymore but are the brake/rear lights double filament bulbs? My mate had a problem once, not on a Golf, where every time he braked his headlights flashed. The cause of that was the brake light filament of the double filament bulb was touching the rear light filament.

This is assuming you have the lights on!

[Greigzy]

Unfortunately no - all lights are turned off, and the brake lights still illuminate.

Have done a scan on vagcom - no fault codes 

[doylebros]

Unfortunately no - all lights are turned off, and the brake lights still illuminate.

Have done a scan on vagcom - no fault codes 

Has anyone fitted any replacement bulbs lately?

[Greigzy]

Last time was around 2 months ago and that was for both front bulbs, and they were replaced with OSRAM nightbreakers.

The brake lights seem more recent, within the last week.

No LED bulbs are fitted to the car either.

[doylebros]

Start by removing both brake light bulbs one at a time to see if the fault changes if that doesn't't change anything I strongly suspect the high level brake light is defective and a new unit will solve the issue the link below is worth a read.

http://www.golfgtiforum.co.uk/index.php?topic=121067.0

[Greigzy]

So, drove the car this morning and when I got to work, the lights stayed on, even after the key was removed.

Despite trying yesterday, I removed the brake light switch, which has made it turn off. Yesterday, this was not the case however 

[Greigzy]

Found a blown fuse in the engine bay (F39 – engine oil temp sensor). Replaced it and on ignition and start up the brakes lights don’t come on, however now they don’t come on at all when the new switches (both VW and ECP) are pressed.

The lights then come on if the switch is removed. If the original switch is installed the lights stay on and do not go off at all.

[Greigzy]

So we are partially fixed.

Read something online that the switch couldn't be pressed on it's own and needed to be on the brake pedal.

Did this and hey presto! Working brakes!

They worked until half way home when I realised they were on all the time. Replaced the fuse again (F39) and it works a treat again.

Now have to work out why it is blowing

[Greigzy]

Still searching and found this on VW Vortex:

Fuse 39 (on fuse panel B)5A -F47-Brake Pedal Switch 87a

This makes a lot more sense as to the fuse blowing. Just need to work out why now!

http://forums.vwvortex.com/showthread.php?2868016-Complete-Fuse-and-Relay-assignments-for-the-2006-2007-GTI

[fab5freddy]

I had this problem when I had my brake master cylinder changed, have you tried the brake switch on the bottom of the master cylinder? Mine wasn't connected back up properly and was causing the same problem as yours, maybe some broken wiring? @Greigzy

[Gow3l]

So this is still a issue, hall sensors replaced and still blowing the fuse 39