My S2K seems to have a mind of its own. Sometimes the doors automatically re-lock themselves despite being opened. I would expect them to automatically re-lock after unlocking if a door is not opened, but this is not the case.
If I open the trunk using the remote fob, the doors also unlock. Then, after a short while, they lock again. In the time between, I can get into the car and the doors will lock themseleves before I have put the key into the ignition.
Once or twice, this has triggered the alarm.
Most days, I now re-unlock the doors with the remote fob, and then there's no problem.

Any ideas?

 

A possibility would be a sticky door switch, so the car doesn't think the door was opened.
Does the overhead light come on when you open the doors?

 

Check out this link. http://s2000.club/OM/DIY%20How%20to%...n%20switch.pdf

This should take care of your issue.