yes, i rewired my campervan with a smartcom operating a 100A relay to charge its leisure battery, couldnt recall its exact layout 

 

if the ashtray/12v socket area pops out easy it wouldnt be a 15 minute job

Edited 1 April, 201511 yr by lichfielddriver

A bit of a faff but the smartcom seems the easiest option. My mondeo sockets time out after 15 mins apart from estate socket which stays live fyi

Edited 2 April, 201511 yr by peterposh

It's really useful especially when you have a car vac or want to charge a phone etc without having to use the key...

NB. When the console side trim (by drivers left leg) comes off you have easy access to the 12v socket and wiring.....