Ford Focus mk1 Central locking issue

[taxation]

Hello,

I'm new to the forum so please be gentle.
I have a ford focus y reg, 1.8 petrol hatchback. It's a little bit old and battered but the engine is sound. The problem I have it with the central locking.
With the key fob (remote central locking) all the doors lock and unlock fine.
When sitting in the car and locking the doors on the handle, only the door I was interacting with locks.
When outside the car and locking/unlocking the car with the key in either passenger or drivers side door, it only locks/unlocks the door the key is put into.
When it is warm the issue goes away and it works just fine. Not too many warm days in blighty recently...

Maybe unrelated but there is a white with a black stripe cable hanging out of the door latch on the front passenger side(on the car not the door) that has been taped up but when using the onboard diagnostics which detects the door being opened and closed that door behaves the same as the others.

 

[Belle427]

wierd that, my guess is a wiring issue. When you use the remote the locking control unit will send the signal to all locks but when you use the key i think one of the door actuators sends a signal out.
common wiring failures occur in the rubber boots that go between doors and pillars etc, as you say there is already a wire taped up.
according to my diagrams the white/black cable comes from a door actuator switch which forms an integral part of the system operation.

 

[Mursal]

Does it make any difference if you preheat the fob?
Or have you changes the fob battery?

 

[taxation]

The battery in the fob still works but I swapped with a new battery to be sure.

New development however, the remote central locking has now completely given up.
I've disconnected the remote central locking unit for a couple of hours but the fob still doesn't work.

Is there a way to test whether it is the key fob at fault or the remote central locking unit?

 

[gregers]

ask here,
www.fordownersclub.com
or
www.ffoc.co.uk