Forensic electrickery

[Dave_F]

Ok....sleuths...figure out this one...

Firstly I know it's a ground issue...but where...?

Left blinker works fine.

Right blinker works fine until you step on the brakes....then it speeds up like there is a bulb fault (fast blink)...goes back to normal blink as soon as I release the brake pedal.

Now I do know that when this happens and I do have my lights on...the fog light indicator pulses dimly.

Other than that no other problems.

Any ideas where to look?

[red90]

Look at the grounds for the rear light (at the lights). What happens is the ground wires for the various lights are normally joined together and if you get a bad connection where they connect to the body, power runs backwards through the ground to the other lights. Find the wiring for rear lights. Start on the right side as that seems to be the problem. Remove the connection to the body, clean it up and make sure it is good. Make sure any ground connectors are good.

Which truck is this?

[Dave_F]

Thanks Red 90... What you state confirms what I was already thinking. I'll have a peek later today and let you know.

It is for the 1991 Defender 110 x-mod.

Cheers

Look at the grounds for the rear light (at the lights). What happens is the ground wires for the various lights are normally joined together and if you get a bad connection where they connect to the body, power runs backwards through the ground to the other lights. Find the wiring for rear lights. Start on the right side as that seems to be the problem. Remove the connection to the body, clean it up and make sure it is good. Make sure any ground connectors are good.

Which truck is this?

[red90]

Thanks Red 90... What you state confirms what I was already thinking. I'll have a peek later today and let you know.

It is for the 1991 Defender 110 x-mod.

Okay. All of the rear wiring comes up in the right hand side. It is a busy mess in an ex-MOD with the trailer wiring. All the grounds connect into one or two bullet connectors. Have a good tug on all of the wires. Sometimes the wires are loose in the connector or the bullets are loose or corroded. I think there should be a body ground connection there as well (there is in mine). Hopefully a PO has not done any modifications. A lot of the time, that is the root cause of problems.

One other thing to note is the size of the bullets is not the same as the common ones used in Canada. It is a good idea to order in a bunch of bullets and gang connectors. The stock ones also latch in very firmly and using them results in a lot more reliability over using normal bullets. Factory ones are soldered to the wire, which seems to work well. It is pretty cheap to order in a bunch and have them on hand for repairs.

http://www.autosparks.co.uk/index.php?cPath=129