when i indicate the fog light on my kangoo van appears to want too join in and flash along with the indicator. i am told that it could be a bad earth connection. could somebody please point me in the right direction on how to locate the earth and how to clean it off please!!

Craig Marshall, August 2009

You make a very interesting point les - I think...

P, September 2009

Hi you maybe RIGHT, BUT how many of the so call parts are made of LOOK alikey metal ?....BUT are really Plastic or C/F... (carbon fiber...u know hat i mean....) so insteed on 2.5 mm earth return or better.. ...1.5...or ...no return earth ast all ...unless C/F even so... the restance should be taken into account...sleeping policeman ....knock the bol..cks out out the bat and wiring..over time...so consider this before parting with good money..

les

les, August 2009

The isn't just One Earth point - there will be many of them.

Manufacturers use the vehicle's body as a return path back to the battery to save the cost and weight of wire.

The battery Negative often has a large short cable running to the bodywork - they call this Earth. A light cluster may have an Earth point possibly with a very short run of wire fastened to the bodywork.

Earth points are tucked away all over the vehicle and sometimes they become corroded or the fastening works loose.

People wiser than me often claim that an "earth problem" is the cause of strange happenings in motor vehicle electrics - I have yet to be convinced but have an open mind.

The way I see it is, that if an Earth connection is dodgy all it can do is prevent something from working properly - I just don't understand how a bad Earth connection can make something work that shouldn't be working.

When A is switched on and B starts working as well it smacks to me of a short or a wiring error rather than a bad earth.

As far as your indicators and Fog lights are concerned each Indicator Lamp will probably have its own Earth and probably shared with a light cluster. The Fog lights may have one each but they too may also share the light cluster earth points.

I don't beileve your problem is a bad earth but any earth should make a good contact with the bare metal of the bodywork and be done up tightly. Wire brush, sandpaper or just a star washer to penetrate the paint. If you scratch the paint away it's a good idea to wipe the re-made earth point with Vaseline to prevent corrosion.

Good luck...

Peccavi, August 2009