One brake light comes on when headlights turned on

[tsport2000]

Hi all,

I got a pair of crystal eyes a while back, recently when i turn my headlights on the left passenger side brake light comes permanently on. When the headlights are off all brake lights work fine. I've checked the connectors, wiring etc and all looks fine. I'm a bit lost on what to try now? Has anyone had this problem before?

 

Thanks!:)

[stantheman1]

Are the stop and tail lights combined in one lamp ie twin filament? If so is the 'bulb' fitted the right way round?

Also does the stop light illuminate at full brightness when the headlights are on?

[Stivino]

Have a good look at the earth connections, too.

[bathtub tom]

It's an earth connection, probably around one of the headlamps. What happens is the current can't find a path to earth, so finds the path of least resistance, in your case through a rear lamp. I'd remove any black leads connected to the body around the headlamps, clean the mating surfaces and apply some Vaseline to the bare metal.

[stantheman1]

I would expect to see all the stop lights lit in that scenario. more likely is a faulty stop/tail light, it's not uncommon to have a short between the two filaments from manufacture thereby illuminating the stop light when the headlights are on.

Has the stop/tail light been changed recently?