Indicators - headlights - brakes. Pick two.

[Ben J]

So I'd been having some problems with my indiactors a while ago, replaced the relay and thought all was well. However now often when I have my headlights on and flick the indicator, as soon as i touch the brakes the indicators go off and the two arrows on the dash illuminate slightly. I presume they arent working on the outside either when this happens, but not sure (Im fairly certain I checked and they arent), if they are then this isnt a problem at all.

I'm guessing it's a bad ground or something? But have no idea where to start looking. If this is a sort of common thing and someone could give some advice it would be much appreciated.

[Ben J]

alright so it seems to be a little more serious then I thought, the lights have a mind of there own.

A couple videos explains more then i can so heres some ****ty phone videos

This is with just the left indicator on and the headlights on
[youtube]aGiV_O_0c48[/youtube]

and the front
[youtube]tnqzRBpnKfY[/youtube]

could it be that i have the wrong relay in there or is it still likely a wiring issue?

edit: swapped in old tempermental relay and still has same problem so suppose i can rule that out

[ryana89]

Out of curiousity, what happens when you take the Indicator Flasher (or relay) out so that the indicator circuit does not flash.
Not saying that the relay is to blame but that may help you isolate and figure out things in this situation.
For example putting the idicator on (without the relay/flasher) and then playing around with the brake and headlights.

Really have no clue what's happening here, except the brakes/headlights and indicators are picking up a positive current from somwhere.

PS. Hope I didn't come off as a smartass, just thinking what on earth it could be :S

[Ben J]

haha that didnt even come close to sounding smartass, thanks for the idea. Brakes/headlights seem normal with the relay out, so the problem might be closer to the relay? But then again maybe not haha. My dads pretty good with electronics so might get him to have a look on the weekend.

[h100vw]

The common point for brake lights and indicators would be the rear light clusters. First off I'd disconnect the bulb holders one at a time on the back lights and see what happens.

Hopefully one will stop the problem from happening. Then you need to work out why.

Could be that a bulb is not seated properly. I have seen dual filament bulbs where one filament has broken and is touching the other causing freaky light issues.

Another thought, do you have towbar electrics fitted?

If it's not in the rear lights, the fusebox would be my next guess. Water ingress can do all kinds of things.

Try the back lights first though.

Gavin

[Ben J]

Thankyou very much Gavin.

Will definately check all of this out. I don't think theres towbar electics (well I'd be quite suprised, but I have found a few hidden things in the car already). I searched before i posted this but actually just found someone with a similair problem and it was corrosion on the clusters.

[h100vw]

Mid 80s Ford used to suffer badly in the UK. I am going with the back lights.

The other spooky light snag I had was on my MK3 16V, I forget the exact symptoms but it was connected to the indicators. The fuse kept blowing IIRC. I kept putting in bigger fuse until I got a wisp of smoke from under the bonnet. This lead me to find a wire shorted out under the airbox. The wire support in the pipe from the exhaust manifold to the airbox rubbed through the loom.

A quick taping up and she was good to go.

Gavin

[Ben J]

So guess what, unplugged one of the rear lights and things went back to normal on the other one. Plugged it back in and problem seems to be gone. Maybe something was lose/dusty/corroded or something, not sure, either way all is good now

Cant believe how simple that was.

Thanks again for the help