[edwardmk]

Originally Posted by macafee2

https://caravanchronicles.com/guides...fault-finding/

Although pin 9 shows permanent live, the bypass relay of the car may not allow this to be permanent live. If a caravan is attached, leaving it connected could flatten the cars battery. I think I have mine wired so it is only live when the engine is running.
Pin 10 as indicated should only be live when the engine is running for the same reason.

pin 12 shows as not used, perhaps those of us with towing electrics should wire pin 12
direct to the positive of the battery just for charging.


macafee2

just been and checked, no 12v on pins 9 or 10 without the engine running

I'm pretty sure I don't have a relay on mine because it seemed to be raising the battery voltage. Relay sounds like the correct way to go though.