G60rob 0 Posted November 20, 2006 The right (driver's side) brake light worked intermittently for a while but now seems to have given up altogether. Bulb is OK. Light fitting contacts, tracks all OK, tail light and indicator OK. But there's no voltage on the black/red wire at the right cluster plug when the brake pedal is pressed. Fuse number 20 blew at one point during all this, but has been replaced and not blown again. The left brake light is OK, so I've temporarily run a wire across the rear of the boot from its plug to the right side plug so I've got two brake lights again, but obviously I'd like to trace the fault. I'm assuming the brake light switch is OK as the left brake light works. The wiring diagram in the Passat/Golf Haynes manual shows a much simpler set-up than I've got (it's much the same as my bodge, in fact). The odd thing is, the right plug has four pairs of wires, and there's a cable going across the back to the left side, so it looks as if the left light cluster, which only has one wire to each terminal, should be fed from the right side. But then if there were no power to the right brake light, the left one shouldn't work! Anybody know what's going on? Quote Share this post Link to post Share on other sites
DiTch 0 Posted November 20, 2006 get a multi meter and check that you have continuity { beep test} on the black/ red cable , extend the end of the cable in the boot with alarm cable to the fuse box, disconnect the end in the fuse box and check that you have a circuit ,, then look for a dead short to earth ,, someone may have screwed around in the past conecting extra brake lights on the circuit or putting towing power connections on it , there could just be a bad joint in the cable Quote Share this post Link to post Share on other sites
G60rob 0 Posted November 21, 2006 I did get as far as taking the fusebox off its mountings, but there's such a solid wodge of tight wires at the back that I couldn't get at the brake light connector without a lot of dismantling, and I wasn't confident I could get everything back in place, so I just put it back and tip-toed away... I went to check today that there really was no power to the right brake light because logically it seemed impossible, and would you believe it, it's now working! But for how long? Next time it goes off I'll do some more tests. I'm wondering if the various intermittent electrical faults I've had on this car all date back to when the immobilizer was "professionally" fitted - there's all sorts of ropy-looking wiring behind the fusebox. Wish I had a wiring diagram. As for extra brake lights or towing connections, I know there haven't been any, because I'm only the second owner and the car was practically new when I got it. Quote Share this post Link to post Share on other sites