Towbar Lead Problem

[Rhys2]

Hello Everyone

I'm looking for some helpful advice from you good folk.

I have a problem with my hitch lead that goes from the caravan to the car. When I press the brake peddle the lights on the front of the caravan come on and then turn off when I release the brake. These are the lights that normally come on when I turn the car headlights on.

Has anybody had this problem before and any suggestions what to check to resolve the problem.

Many Thanks
Rhys

 

[Brum1]

Quite simply, for some reason the Brake lamp feed (Red wire in the 7N system) is shorting to either side lamp circuit via a Black or Brown wire. This could be due to a stray strand of wire in either the Black plug or socket.

Another possibility to look at is in the rear lanp bulbs (stop / tail) Have one of these been replaced recently? Maybe an incorrect bulb has been used that is causing the terminals to touch each other.

Hope this helps.

 

[Len_Cuff]

Wouldn't be a Vectra by any chance? Mine does exactly the same thing and I've had all the wiring checked
Seems to be a 'feature' on these cars!!

 

[Trevormc]

It could be one of a number of problems.

Bad earth in one of the caravan back lights. Plug or socket wired wrong. Wire that is not in the holder correctly ie two wires touching either in the plug or socket. Badley coroded conections in plug or socket. If this is a new car or caravan wrongly wired up.

Hope this is of some help.

Trevor

 

[waffler]

A minefield! Almost surely an earth problem. You need a voltmeter- about £6 from Maplins. (YOu could use a bulb and some wires instead but you will have to be nimble- better to get the meter.) Set the meter to 20 volts or similar. Obtain a wiring diamgram for teh socket on the car. There is one on the caravan club web site. Have someone press the brake pedal, with ignition on and use the voltmeter to check the voltage between the two pins, the brake light and return. It should be above 12 volts. If it is then the fault is not in the car. If it less than 12 or worst still zero you will need seriosu help with the car. Now connect caravan to car, if on 7 pin just the black plug will do. Remove the light cluster on the back of the van, check for corrosion- looks like white dust. If so clean connections with emery paper. Check teh earth connection. This is usually just a wire onto the metal base. Check that for corrosion. If still no luck have pedal pressed again and test teh voltage between the connector to the bulb and the earth. The bulb in question will have two inputs so try both. You shoud get a reading of 0 and one about 11 volts. Now look at teh bulb and make sure it has two complete filaments. If not replace it. Hope this helps- patient work.

 

[Rhys2]

Many thanks for your replies everyone...I'll give it a go tomorrow.

 

[Len_Cuff]

What's the tow car? Vectra?