When I press the brake pedal on my tug the sidelights on my'07 Pageant Bordeaux are coming on as well. I've fitted a new plug and socket(suzies) to the car/van and checked all the bulbs. No joy...Anybody got any ideas?
When I press the brake pedal on my '07 Pageant Bordeaux ...
Didn't know the Pageant had a brake pedal ..
Seriously though, have you got means of testing the socket with a voltmeter to check the outputs are correct first; check for 0v on both tail and brake pins, then just process of illumination (elimination) to check what voltages occurs when braking etc.
Where the multicore cable comes into the caravan there is a plug system on Baileys try there first as the plugs can get badly corroded.
To check that it is a bad earth that is the problem run a wire from a good earthing point on your car to the earth on one of your front marker lights if the problem goes away you know it's an earth
------------- Caravanning is a way of getting a cheap holiday out of an expensive hobby