Electricity problem

[Cathelijne]

We took the car for it's MOT today and at the garage they checked the main beam. The head light popped up directly, but the light weakened and the fuel pump went on. After switching the light off, the fuel pump didn't stop. After earthing the relay board with an external earth wire, the fuel pump stopped.

Also when the lights are on, the direction indicator gives also a bit of light.

They are looking for the cause nearly a day now, so we are broke if they don't find it soon. So please help us!

[tallbloke]

Cathelijne, Maybe you already have part of the answer. Fibreglass cars often have problems with earthing points. Check your earth connections are clean and tight.

Hope this helps

[Gerry Attrick]

Agree. It sounds like an earth problem. Perhaps now is a good time to go around all of the earth points on the car, clean them up and apply some grease. Not only could you cure the current problem but you may stop others appearing in the future.

[Cathelijne]

The problem is that we don't know how to recognize earth connections. Are they on the relays, or do you mean the big wire on the chassis?

Another cable is connected with the engine, do we have to clean this one too?

[jeff m]

Earth or ground wires are black.
The braided straps are also grounds but are less likely to be your problem as they would affect your starter motor first. (high current flow)
Start looking for the prob with a long ground wire from the battery (-ve). turn on your headlights put the ground wire on a black wire near the headlight, if your headlamp glows normally you have found the missing ground.
Don't be confused by other things that glow dimly that is just the 12v trying to find another ground.

I do hope you don't have an all black wired car.

[Cathelijne]

jeff m said:

Earth or ground wires are black. I do hope you don't have an all black wired car.

I have....
It's going to be difficult. At the garage they found a bunch of burned wires.

It's a pity it happend at the MOT, it has to be ok to get it's approval

>> Edited by Cathelijne on Tuesday 9th November 10:50

[jeff m]

All is not lost

But you can't use a "full ground"

Use a 12v test lamp from a ground, it will be much more difficult and you will not get a full glow in your headlamp but it WILL get brighter when you are on the correct ground run. When it does then you can put a "full ground" on it to prove it.

[Cathelijne]

It's done! They were busy with it for 18 hours, but it's working again (and paid )

>> Edited by Cathelijne on Thursday 11th November 19:14

[tallbloke]

Wahey! Good result.

Sorry to hear you are broke now

But at least you can

You must be able to find a few euros for a celebration