I have a Focus 2005 Titanium with keyless entry with a strange problem. When I lock the car with the fob (or the keyless knob on the door handle), it very often unlock itself after a while, all doors simultaneously.
When I open it with the fob, (or the keyless system), it most of the time locks again when ignition is turned on, or when the car starts driving. (But not always) And it can lock / unlock itself for several minutes with the ignition on. It can stop doing this for a while, and start all over again on the same trip. All doors at the same time.
It seems like if the doors are locked with the key, it will not unlock again. Not so often, anyway.
Any ideas? I have been thinking of faulty receiver for the remote key (where is it located?) or the GEM module. Or maybe the lock / lock actuator in one of the front doors. (If so, how to find which one?