Ive got a problem with the tailgate lock on my 3dr, it wont lock with the central locking i afto keep using the key to unlock it, ive changed the solenoid & checked the wiring as anybody got any ideas

 

is the solenoid attached to the lock?

Does the soleniod attachment move when the barrel is turned? Manually actuating the soleniod should lock the system, the same for unlocking.

 

The solenoids do play up but check the wiring as it passes through the body to tailgate as the movement here will often break the wire, INSIDE THE INSULATION, done a few escorts broken here, grab ends of wire and try to pull apart and you will soon see if the wire is broken inside.
tabetha

 

Yes the solenoid is attached to the lock, & yes the attachment does move when the barrel is turned

 

You need to check it is moving FULLY, the solenoid pulls on a little linkage that rotates a circular piece of metal at the end of the lock barell, if it cannot move fully(partially seized) this will give what you have, just take lock out and it is easy to see how it works,.
As the circular piece moves(rotates) it ligns up a CUTOUT section of it which allows ther pluger(lock button) to be depressed.
tabetha