In January I had a towbar fitted. At the time I didn't have a trailer but when I did attach one some of the lights on the trailer didn't work and the rear nearside side light on the car went out after a few seconds. I had the car checked by a Skoda dealer who said the towbar electrics were at fault. The guy who fitted the tow bar came back and fitted a 'bypass', which seemed to do the trick.
However now I can't turn the headlights off, even when the trailer isn't attached. As soon as I turn on the ignition the headlights come on, low beam and so do the rear side lights. The front side lights don't come on now and I don't have any parking lights. When the trailer is fitted and I press the brakes the side lights on the trailer glow more brightly but the brake lights don't work.
Can anyone tell me what's going on?