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BLKWDW
8th May 2012, 06:46 PM
Hey all i've recently noticed a problem with my right hand tailights on the gq. The brake light works fine the parker light works fine but when you brake whilst the parker light is on the whole globe goes out.
Any reason for this.

BearGUST
8th May 2012, 07:01 PM
Try changing the globe.

BLKWDW
8th May 2012, 07:22 PM
I have i swapped the left hand globe over and it done the same thing.

Clunk
8th May 2012, 07:26 PM
Sounds like you've got a short somewhere, hopefully one of the electrical gurus will help.

Yendor
8th May 2012, 07:33 PM
You have an earth problem at the right hand side tail light.

Either the socket that the bulb pushes into is corroded or the earth wire that runs to that tail light is broken or has a bad connection.

If you look closely at the bulb when the parks lights are on you will see that both filaments inside the bulb are glowing, when only one should be.

BearGUST
8th May 2012, 07:37 PM
OK, have you got a test light?
If so, get a good earth point and check the centre contacts while someone puts their foot on the brake. If the test light glows you've got an earth problem.
If the test light doesn't glow you need to look why it's not getting power.

BLKWDW
8th May 2012, 08:45 PM
You have an earth problem at the right hand side tail light.

Either the socket that the bulb pushes into is corroded or the earth wire that runs to that tail light is broken or has a bad connection.

If you look closely at the bulb when the parks lights are on you will see that both filaments inside the bulb are glowing, when only one should be.

No mate when the parkers are on only one filament is glowing and the other one glows when the brake is applied. When the filament is glowing with the parkers on and you press the brakes it goes out and the brake doesnt come on.


OK, have you got a test light?
If so, get a good earth point and check the centre contacts while someone puts their foot on the brake. If the test light glows you've got an earth problem.
If the test light doesn't glow you need to look why it's not getting power.

No but looks like i'll be getting one. I cant see why it doesnt have power as it works when the parkers arnt on.

Yendor
8th May 2012, 08:56 PM
Get yourself a length of wire strip back both ends, put one end on the bulb housing (not the pins at the end of the bulb) and the other end connect to something metal, make sure it has a good clean connection.

Now retry your lights.

garrett
12th May 2012, 01:11 PM
i had a problem like this when i took the wiring harness out a few of the cables were nicked and touching so i rewired the harness, problem solved

garrett
12th May 2012, 01:12 PM
as in the harness on the back tail lights

BLKWDW
3rd June 2012, 05:15 PM
Alright i'm in the process of rewiring the rear of the car. After pulling all the tape of the wiring for the lights and trailer plug clearly the bloke had no idea. The earth wire for the tailight/brake light was wired to the electric brake wire on the plug and 4 of the 7 wires wernt connected to anything. Once i earthed the the light it worked fine now just need more wire to fix up the rest of the trailer plug.

Lieney
3rd June 2012, 06:55 PM
The lights that have two contacts on the base (generally) eg brake / tail globes have three connections.
1 - earth through the body.
2 - positive delivery of 12v for park
3 - positive delivery of 12v for brake.
When both brake and park are activated, they current from each side cannot flow anywhere, thus effectively cancelling each other out. (the current cannot flow, thus no light is present.
When park or brake only is on, the current flows from the delivery wire through one filament (either brake or park) and then continues to flow through the other filament in that globe, then earths out on the other light assembly or somewhere in the wiring.
The earth on that side is no longer there / decent.
As yendor stated, create an earth by stripping a serviceable piece of wire and 'make an alternative earth. Then try again.
Electrical work can be fun

Robo
6th June 2012, 02:53 AM
Trailer plugs are really a pain in the you know where.
If the job is done correctly first up, yrs of trouble free motoring.
how many trailers do you see no lights etc.
crimp lock fitting are the quick and easy choice but usually give trouble either cutting the wire or losing contact.
strip solder and self amalgamation tape is the slow, but less troublesome choice.
a little dab of solder on end of wires also makes securing the wire inside the plug fittings less prone to snapping off, coming lose falling out .

Fitting tow bars helping ( was one of my very first job as a teen) I've done a couple lol.
cheers