1990 integra no tail lights

Having some problems with my taillights. Rear tail lights work when
engine is off,but stop working once i start my engine.No problem with
headlights or brake lights.any one had this problem..

Bill Gavin 1990 Acura Integra

 

Leave the engine off when you drive...

 

Any aftermarket additions or modifications of ANY kind to ANY of the
wiring?

 

This was a used car i bought 1 year ago.It does have a after market
stereo installed.Lights worked fine until last week.Do you think this
might be part of the problem.I will take it into the dealership next
week if i cant figure this one out.

Bill Gavin

 

Joe you have a good sense of humour.

 

Are the lights working or not really tied to the engine being running or
really tied to the key being in the on or run position?

Maybe pop the stereo out and inspect the wiring. There is a wire (on most
stereos) that ties into the lighting system to tell the stereo if it should
dim it's display. Could an an issue in that circuit.

My first suspicion (not being able to see the car) based on what you've said
so far is a sloppy wiring job behind the radio.

 

I'm with Seth. Somebody's done a lousy wiring job.

You need to check all the wiring behind the dash /very/ carefully. Chances
are pretty good you'll find some wires that have been twisted together and
are coming apart, or are crossing circuits, or something like that.

Don't forget to check the fuse box. Some people try to take power from
there by stuffing a wire under one leg of a fuse, which makes the fuse
loose.

Power to the taillights is from from the red/green wire that comes out of
the headlamp switch behind the steering wheel and goes to the #11 fuse.
After the #11 fuse, that wire becomes red/black. The side markers and the
license plate lights all use the same power source as the taillights.

You likely won't be able to remove the steering wheel nut without an impact
wrench. But once you do remove the nut, the wheel just slides off; the
splines are not tapered.

(Every thread like this is a reminder to me of why I refuse to purchase any
car that has had any sort of alteration to its electrical system.)

 

This ones driving me crazy.Checked #11 fuse it is ok.
Should I pull the stereo out when the tail lights work and the stereo
works when the ignition key is in the aux position.Do stereo installs
usually take there power from the tail light circuit.Any more ideas
would be welcome.6 HRS wasted alredy

Bill Gavin

 

I did not say the fuse was blown. If it had been, the taillights would not
work at all. Nor would the side markers or license plate lights.

Yes. Somebody has done a crappy job of wiring /something/ in that car,
whether it's the radio or something else. When dealing with aftermarket
modifications, all bets are off.

From where did the installer take the power? From wherever it was
convenient. Or from the first wire that made things work instead of just
making magic smoke and blowing fuses.

Is this your first car? If so, this one will be quite a learning
experience.

The problem with aftermarket is primarily that the factory didn't do it.
Aftermarket modifications are often performed by young, impatient,
inexperienced, greasy-fingered knuckle-dragging apes with no wiring
diagrams, no manuals, and no electrical knowledge.

If you've spent six hours on this and not bothered to remove the radio in
all that time, then you need the services of a professional. Or at least
those of somebody with an inkling of how automotive wiring is regularly and
repeatedly botched in exactly the same way, each and every time, by the
above mentioned simians.

 

Yes, pull the stereo right now and see what it looks like back there.

If it is just an aftermarket stereo and no additional stereo items (amps,
equalizer, etc...) then I wouldn't be too concerned about tracing back to
the fuse back or any of that as for a simple head unit swap everything can
be done with what's in the stereo cavity.

When you pull the stereo, did the person who put it in there use an adapter
harness or did they just cut the stock wiring to wire in the new radio?

If the cut method, then you have a rats nest to untangle. If they used a
harness, then your issue may be as simple as some electrical tape and/or a
wire nut came loose.

Pull the stereo, take inventory of what you see and start from there.

 

6HRS wasted including internet time.
Took the stereo out today Alpine.Looks like a adapter harness was
installed to the factory plug.Next with the stereo unplugged I tryed
the lights still no luck.Doesnt look like factory plug has been
spliced or touched.Is it possible problem could be in the ignition
switch or the light switch.

Bill Gavin

 

I gave you wire colors and a connector location.

Plus I gave you another clue: Check to see if the side markers and license
plate lights work.

 

At this point I would bet money it's a bad ground. With the engine off, the
lights are getting their ground through some circuit that is off with the
engine off (question about if this is truly tied to the engine running or
just the run vs. accessory vs. off position of the key switch hasn't been
answered yet).

But I'll bet it's similar to the situation that happens sometimes where a
persons brake lights only work when the headlights are off or the tail
lights work only when the brake pedal isn't pressed.

Bad ground.

 

I considered a bad ground as well, but dismissed that as being unlikely.
The grounds are on the interior of the body shell and are rarely defective.
The one exception is the taillight ground in the hatchback. That one is
sometimes damaged in bad rear-end collisions.

Power to the taillights is switched. Ground is permanent. This is the
opposite of the horn circuit, where the horns are always live and ground is
supplied by the horn contacts in the steering wheel.

In any case, if the OP would check his front marker lights and rear license
plate lights and see if they behave the same as the taillights, that would
give us a clue. The markers and taillights use different grounds, but the
taillights and license plate lights use a common ground.

Actually, the same power source feeds:
radio
taillights
front markers
license plate lights
glove box light
heater control panel lights
clock
cigarette lighter
and many other things. These use many different ground points.

 

I just had another thought: Suppose the aftermarket radio installation
included an amp in the rear of the vehicle. In that case, there would be
tampering of the wiring at that location. Somebody might have even spliced
in an aftermarket power antenna.

 

I see your point. But as a former after market installer I have seen this
way too much. Often times (mis) blamed on the stereo. On many of these
cars a few items use a shared ground and if the grounding bolt has worked
itself loose or rusted (this is an almost 20 year old vehicle) it becomes a
"floating" ground that is no longer ground when the 2nd circuit is also
energized.

Could be either... My money is on the ground.

 

The puOn Sat, 10 Oct 2009 20:07:11 -0400, "Seth"

Ok some more clues.

1. all lights work with ignition in off position,when key is in aux or
engine running I have no side marker lights,liscence plate light or
tail lights.clock and heater lights work.
2.Lots of rain the last few weeks some condensation in back tail light
lenses.
3.car is a hatchback with no damage.
4. Car is worth the effort 20 years old seen winter twice no rust
197000km.

Bill Gavin

 

Then it's very unlikely to be a ground problem. I've got the wiring
diagrams here and these problems have only one point of commonality: the
power feed (red/blk wire); the grounds are in totally different locations.

Just in case, pull the large trim panel off the rear of the hatch interior
to expose that ground bolt for inspection. The other ground is in the
engine compartment right beside the windshield washer filler neck.

I still think there's some botched wiring in the dash or steering column.
Pull the steering wheel and have a look at the wiring there. Follow the
red/blk wire from the steering column switch as far as you can (as I
originally suggested).

Taillight gaskets are bad. Check the bulb sockets for severe corrosion.

No rust, no collisions, for sure? Then the grounds should be perfect,
provided they've not been altered. Hondas generally do not exhibit ground
problems when the factory setup remains unchanged.