One light always on

Have a '92 Volvo 240GL. The right rear brakelight is the problem.
When I put the bulb in with just the car lights on, all lights are fine
except for the right brake light. It is lit up in the "brake applied"
position(brighter than the normal taillight). When I push the brake
with it like this, the fuse blows. The circuit board was pretty old
and raggy, so I have replaced it and problem still exists. Both brake
lights are new. I can't figure out what is causing this? With the
right brake light removed (this is the only way I can press the brakes
without blowing the fuse) everything works fine...including the left
brake light and the 3rd (rear window light) brake light.

Can anyone help me? I don't know what is going on.

 

Look at the wiring inside the car, it's possible one of the wires has chafed
and is shorting to ground.

 

check wiring in trunk especially if any lights are in truck lid itself the
wiring there likes to break especially if you tend to load the trunk full
may have pinched a wire to ground on the truck hinge common problem with
toyota's too.

 

Something is screwed up in the way the taillight is wired, or maybe you
have the wrong bulb holder. What you're going to have to do is compare
your taillight circuit boards, and make sure that the bad one is an
exact mirror image of the good one, right down to bulb holders and which
wires connect where. Removing the taillights from the car may be the
best way to accomplish this.

--
Mike F.
Thornhill (near Toronto), Ont.

Replace tt with t (twice!) and remove parentheses to email me directly.
(But I check the newsgroup more often than this email address.)

 

I vote for the holder. Wiring shorts should blow the fuse regardless of
whether the bulb is in or not, unless I'm missing something.

Mike

 

I thought about that too, but I used the left brake light holder for
the right and it still does the same thing. I can't tell any
difference at all between the holders, but I could be wrong.

 

Are you sure you have the right bulbs? For example, dual filament bulbs
instead of single filament?

Mike

 

Yes...I even bought 2 new bulbs to make sure nothing was wrong with the
bulbs.

 

Be sure that isn't like still getting a wrong number when using redial...
they should be dual filament (two contact patches on the end instead of
one.)

Did this just start one day, or was it after changing something?

Mike

 

Going up a couple of posts... The bulb holder for the brake/tail should
be noticeably different from left to right, black on the left and white
on the right. (All other holders should be black, and identical from
left to right, and this info only applies to sedans, wagons use black
holders all around.)

--
Mike F.
Thornhill (near Toronto), Ont.

Replace tt with t (twice!) and remove parentheses to email me directly.
(But I check the newsgroup more often than this email address.)

 

Hmmm....I actually have all black holders. It has been working for
many years with those holders though.

Car is actually my girlfriends, so I don't always have it to work on or
check things out.

Problem just started to happen, I didn't change anything. I am leaning
more towards a short somewhere as well. The wires are in a plastic
type tubing and are tucked away pretty good, so it will be tough to get
to them. I would love to have a wiring diagram to help out though.

 

Actually, all the bulb holders are black. The problem just started
happening. It is actually my girlfriend's car, so I don't have it to
work on all the time. I think it has got to be a short somewhere
though. I need to try and find a manual for it to see some wiring
diagrams.
Does anyone know if the wiring to the right taillight is feeding from
the left taillight...or how it is run?

 

With the wrong holder (assuming a 3 contact holder for a double filament
bulb), all that happens is the taillight comes on during braking and
vice versa. Both taillight and brake lights are fed separately from the
bulb failure relay, which is under the dash, so they have their own
wires. (Left and right taillights are even on different fuses.)
There's a third "tail light" wire that bypasses the bulb failure relay
used for the license lights.

license light - white
left tail - red
right tail - brown
left brake - yellow-gray
right brake - yellow

My guess is the bulb holder is either defective (2 of the metal
conductive strips are touching) or the part of the metal contact strip
that touches the circuit board is bridging 2 circuit board traces.

--
Mike F.
Thornhill (near Toronto), Ont.

Replace tt with t (twice!) and remove parentheses to email me directly.
(But I check the newsgroup more often than this email address.)