New 13 pin socket won't power caravan rear lights

[Hannahleaning]

Hello,

I hope someone can help! We have just had a tow bar fitted for our ford S-Max with a 13 pin socket. It all tested fine at the garage where we had the work done. However when we hitched he caravan up, no lights at all work on the caravans when we hitch up using a split adaptor to the 7 pin sockets on another car, it works fine... So the caravan wiring is all ok, and the wiring in the car lights up their test board, but together it's not working.

We are very confused! Can anyone suggest anything? The caravan is a sprite major 6 sports style 2010.

Thank you in advance

 

[Hannahleaning]

We saw a post regarding realigning the 13 pin socket, we have done this, but it still isn't working!

 

[WoodlandsCamper]

Can you take the car and caravan to the towbar fitter so they can check?

 

[Hannahleaning]

Yes, just concerned about driving it around with no lights or indicators! Plus they are now shut and we wanted to go away in it tonight. We were hoping there may be something obvious that we are missing

 

[GStockton]

It sounds like the earth return wire for the lights is broken or not connected in either the 13 pin socket or the other end of the cable within the vehicle. you will find it is a WHITE Coloured wire.

 

[GStockton]

Another thing to check is 1 does the caravan fridge work on 12volt with the car engine running? and do the internal caravan lights work when plugged into the car without the engine running? I ask because the fridge and internal lights have separate earth returns to the road lights.

 

[Hannahleaning]

Thank you so much, the earth wire was the problem and it's now fixed - thank you so much

 

[ApuljackEngineering]

This does, of course, beg the obvious question of the usefulness/integrity of the test board the fitter was using!