[reworht]

Originally Posted by macafee2

13 pin towing socket wiring

Here is a link to the socket wiring
https://caravanchronicles.com/guides...fault-finding/

and here is a link for a habitation relay but you will need to scroll down
https://www.campingandcaravanningclu...ectrics/page7/

link to TEC 3M relay wiring, again scroll down
https://www.ebay.co.uk/itm/Self-Swit...-/141896362193

I understand that if you have Al Ko ATC you need pin 9 permanent live but if you don't have ATC, why would you want pins 9 and 10 permanent live?
If the caravan is left connected to the car and not on mains hook up, for example on a ferry, by pins 9 and 10 being permanent live you can flatten the cars battery. Newer cars and caravans but I don't know what age should have relays to prevent this but our cars are not new and I am not convinced my caravan has a habitation relay

I have just checked one of my cars, pin 9 is permanent live, charging the leisure battery. If the fridge is set to 12v, not on electric hook up and engine not running, am I right in thinking the fridge will draw power from the leisure battery and in turn the car?


macafee2

As far as I know, the fridge cannot take power from either the on-board battery or from the car's battery. The only time the 12v feed to the fridge is operative is when the car's engine is running and the alternator is pumping out power.