ford focus 55 plate

I have a 55 plate 5 door ford focus (uk model) when I press the brake pedal the tail gate opens I have checked the wiring around the tail gate and light clusters all seem okmick

If you have a friend that's into mobile electronics, slap him and make him fix it. I have to assume it's a negative ground system still. Perhaps there is enough power flowing back into the ground around the tail light and down to the hatch latch, which gets it's ground through the wire. I'd try taking the bulbs out of the brake lights and see if it still happens. If so, I'd think you had a ground problem in that area of the body. Otherwise it's going to be GEM/Body computer error most likely.

it had to go back to the ford main agent .....he changed the boot lock .......???..I would love to know have it's connected to the brake light circuit ....but it's workedmick

I would suspect the new one has a diode in it to stop the problem I described. Just a guess though.