A few days ago I queried a problem with 'jumping locks', which seems to be caused by wear in the driver's front door latch so that the CDL microswitch isn't reliable pressed in to apply the earth condition to keep the doors unlocked during motion. Until I have the time and inclination to remove the lock and investigate, I decided to travel with the doors locked by depressing the sill-lock, thereby creating a stable condition. Imagine my surprise today when the sill-lock was depressed and nothing happened to the other locks at all! We completed a short journey with no jumping locks, parked the car and I locked it with the fob. All doors locked. Later I returned to the car and unlocked it with the fob, started the engine and tried the sill-lock again. Nothing. We returned home and I locked the car with the fob. All sill-locks down. How can that happen when, as I understand it, the same microswitch is unswitched whether the car is locked electronically or physically? I should add that we tried pushing the sill-lock on the passenger door down and that didn't do anything either.

Whether the door is locked electrically or physically what happens is the motor moves the mechanism to lock and that is what causes the button to go down. It makes no difference how it is moved, just that it is and at that point it should operate the CDL switch which it obviously isn't.

That's what I thought. I just can't understand how that could be.

One thing to bear in mind, the drivers CDL switch provides the ground for the tailgate so if it is faulty you either won't be able to open the tailgate or it won't lock.