12S plug on caravan

[Barbara_45]

Recently purchased 1992 caravan. Can the 12S plug be converted to fit 2004 car, as at the moment the car will not charge the caravan battery.

 

[Ancientcaravanner]

We need a bit more information. Is the layout on the car a single 7 pin socket, two 7 pin sockets, or is it 13 pin? Is it a single plug on the caravan?

 

[Barbara_45]

Hi Ancient Caravanner, there are two plugs on the caravan, one grey and one black. Two on the car one grey and one black. The black one works fine but the grey one will not charge the battery, but will turn on the lights in the caravan when running. Hope you can help.

 

[Ancientcaravanner]

Pin 6 on the 12S (grey plug) carries the voltage for the fridge and pin 7 the return earth and pin 2 is the voltage feed and pin 3 the earth for the battery charging. Between 1988 and 1989 the wiring changed see:
http://www.a-tconsulting.co.uk/caravan_tech/12nschanges.html

they give a description of the changes. As your car is pre this date you may need some changes. So the first thing to check is are there volts across these pins. Remember there will only be volts measured between pins 6 and 7 and (2 and 3) when the car engine is running as there should be a relay in the line that only closes when the engine is running - this stops you draining your car battery when you switch off the engine.
If you don't feel confident to do this job get a mobile fitter to sort it.

 

[John_miller]

Have you used your car to connect successfully to a previous caravan? I ask because some towbar fitting places do not automatically fit the necessary relays to charge the battery and run the fridge as the job then becomes much simpler.

John M