rear tailgate lock not working

[adpsimpson]

Not quite sure what you've managed to eliminate here, but if you're convinced that the switch is working and convinced that the motor is working, then that leaves only the wires between the switch and the motor. So really, the problem is solved - fix the wires.

Of course if the wires are ok, than either the motor or the switch is not ok.

Have you tested the wires for continuity? Have you, as suggested, connected one or the other of the live wires at the switch to earth, to simulate the switch? If so, what happens? Why are you convinced the switch is ok? Although I'm no expert anyway, it's very difficult to figure out what's happening when only half bits of information are given (that's probably why the actual experts have fallen silent).

[solberg1]

hi yer i have striped back the wires and earthed them and nothing happens.i no it definately isnt the key lock because the barrell itself moves left to right and turns a plastic switch from earth to earth.theres no contact or live contact at the barrell at all.ive put a multimeter on the contacts at the swith end and get a supply both sides.havnt tested between tailgate hinge and relay yet,(im only assuming it goes to the relay).the motor does work as its new and goes up and down with switch inside.cant work it out as theres power to the swith and motor.but then again im not an auto electrician.but no enuf to get buy if you no what i mean!

[nero279]

Well finally we're getting somewhere then, you're answering the questions asked of you, and following the advice given on how to test it.

So, the fault is more than likely with the relay box behind the passenger side boot trim. As what you've now done is eliminate the switch. And because you have +12v at the switch you can fairly safely assume the wiring from the relay box to the switch is ok, if the wire was broken you shouldn't get +12v at the switch. I would suggest the next step is to repair or replace the relay box.