We have just bought a “new to us” 2017 Volvo XC90 with a retractable towbar. Our van has a 13pin plug that twists when inserted into the car. On the new Volvo the socket doesn’t have the “twist” can you get a straight push in plug? Hope this makes sense!!!
------------- "Money can't buy you happiness but it's more comfortable to cry in a Mercedes"
Think you'll find that the 'twist to lock' is part of the specification for 13 pin plugs/sockets under International Standard ISO 11446, so if yours doesn't then either non-standard or broken.
Seem to recall that plugs can end up with the pin carrier part 'out of sync' (incorrectly rotated) with the body which prevents engagement with the socket, there is a simple plastic tool available that can bring them back into correct alignment. Could it be either your plug and/or the new (to you) socket have been mangalated to get them to mate without the 'twist'!
If a new plug or socket are required, they are only a few pounds each, and not too difficult to fit for a competent DIYer.
It could be the car has only a seven pin socket fitted. The previous owner might only have towed a trailer.
In which case a new socket will have to be fitted along with a new loom especially on that particular car, if you want your fridge and battery to be powered whilst towing.
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