E30 Zone

my central locking unlocks itself a few seconds after i lock it. anyone know what the problem could be?.. thanks ('90 325sport if that matters)

Mine does this, it can vary from 30seconds to a few hours after locking. I'm assuming it is the locking mech gumming up and I know that the driver and passenger locks need a rebuild on mine, hence my assumption.

Very annoying though, should sort it but been putting it off. If someone comes back with a known reason for this (rather than my assumption), it'd be good to hear.

Assuming it's not some aftermarket alarm acting up, the locking ECU thinks the driver's door isn't shut.
The reason will be wear in the linkage inside the door, probably compounded by 23 years of lack of lubrication. Try adjusting the lock motor slightly in its slotted mounting holes.
If the wear is too great, you won't be able to cure the problem without causing other issues.

thanks brian.. it does have aftermarket alarm, so that could be the problem.. still does it when i lock it with key without setting alarm though, so i took it to be a CL problem.. i'l try the motor 1st.