Electrical: L brake light dead when headlights on

I hope someone here will be able to give me a quick diagnosis.

This is a 97 Nissan Sentra.

If the headlights are on, the left brake light doesn't work. The tail
lights, right brake, center brake, and turn signal lights all work all
of the time, and if the headlights are off everything works.

Suggestions?

Thanks!

On most vehicles, that means the bulb has shorted out or the fixture has
lost it's ground. I would check the bulb first, then check how rusty
the screws are that hold the fixture or any black wires bolted or
screwed on close to the light fixture along the harness.

Mike
86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
88 Cherokee 235 BFG AT's
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wrote:
>
> I hope someone here will be able to give me a quick diagnosis.
>
> This is a 97 Nissan Sentra.
>
> If the headlights are on, the left brake light doesn't work. The tail
> lights, right brake, center brake, and turn signal lights all work all
> of the time, and if the headlights are off everything works.
>
> Suggestions?
>
> Thanks!

maybe bad ground connection on the left brake light

Mark

wrote:
> I hope someone here will be able to give me a quick diagnosis.
>
> This is a 97 Nissan Sentra.
>
> If the headlights are on, the left brake light doesn't work. The tail
> lights, right brake, center brake, and turn signal lights all work all
> of the time, and if the headlights are off everything works.
>
> Suggestions?
>
> Thanks!
>

First thought would be a bad ground in that taillight assembly. Does it
try to "wig-wag" when you stand on the brakes with the parking lights on?

nate

--
replace "fly" with "com" to reply.
http://home.comcast.net/~njnagel

I just tried it with the parking lights on. It's the same. Left brake
light is out. I'm not sure what you mean by "wig-wag." With the
lights off, everything is fine as described above.

There seems to be a consensus that there's a bad ground in the tail
light assembly. How would you troubleshoot that? For what it's worth
I've already tried a known "good" bulb (the one from the other side)
without success.

Thanks for any help!

> This is a 97 Nissan Sentra.
>
> If the headlights are on, the left brake light doesn't work. The tail
> lights, right brake, center brake, and turn signal lights all work all
> of the time, and if the headlights are off everything works.
>
> Suggestions?
>
> Thanks!

It sounds to me like you have ground except when you turn on your
headlights. I would check the ground in the headlight or find a common wire
that links the headlight and the left taillight. My guess would be the
headlight switch isn't any good. I have a similar problem in one of my
trucks where if you turn on the headlights, you lose the console lights, but
all else works, and I know for a fact that it is the headlight switch. I
just haven't gotten around to changing it yet because basically, I don't
drive it at night. These can be tricky to find.

Good Luck

Fwed