Freelander TD4 3 Door 2002

Hi All
Had some odd things going on with my Central Locking?
When I first got it 18 months ago the central locking only worked on the drivers door, not passengers or rear.
Then bizarrely one day, it swopped over!
Now the other way around

It may be coincidental, and perhaps the drivers door lock has failed at the same time as the other doors decided to work.... I had it checked and there were no error codes?
Any ideas, I know on some other makes there are mechanics tricks (such as hold certain buttons together) I can feel some funnies comin on

Cheers for now.......