To do this you need to establish which wires do what on your car.
Start by removing the drivers door panel and peel back the vapour barrier at the top where the lock assembly is.
You will need a test lead. A multimeter will help, but a test lead will actually operate the locks while you are testing.
I can only tell you the colours on the Disco door lock as its the last LR car I worked on, as far as I remember all Rover cars use the same colours BUT CHECK.
With the drivers door open, trick the lock by pushing the cam back with a screwdriver so it is in the door closed position.
Operate the door pin and see if the doors all lock and unlock. If you haven't tricked the lock they will bounce.
Pull as much of the loom to the locking motor, out of the door as you can.
On the Disco 1& 2 you can get to the connector by pulling the loom behind the speaker.
FOR THOSE WITH A HAYNES MANUAL THIS IS ALL IN CHAPTER 12.17
Connect one end of the test lead to earth and probe the connections in turn as you operate the door pin, record what happens as you lock then unlock.
Pink: Should flash live as the door locks or unlocks. NOTE WHICH
Orange: Should flash live as the door locks or unlocks. NOTE WHICH
Red/
Pink: When you touch this with the test lamp the doors should lock.
Yellow/
Orange: When you touch this with the test lamp the doors should unlock.
Black: should be either 12v or earth, Check this with a meter.
Depending on the fault, you can replace the whole motor with a 5 wire Spal one.
The wires SHOULD correspond like this.
[The reason I say should, is in my 15 years as an auto-electrician I learned that no manufacturer ever sticks to the same wiring colours for ever, so I never assume, I always check]
Pink===============
Red
Orange=============
Blue
Yellow/
Orange========
Brown
Red/
Pink============
Violet
Black===============Black
The Spal motor should line up with the holes in the lock plate but you will need to use longer self tapers and washers to hold it in place, You may also need to ease out the hole in the end of the actuator as LR use thicker rods than the aftermarket locking motors.
You can cut and join the wires with crimped sleeve connectors (Butts) but I prefer to solder and use heat shrink.
Reassemble, test and don't forget to pull the door handle to un-trick the lock before you slam the door shut.
If you are not savvy with car electrics this is a job best left to others.
