I have done a search on this site first, but still need a bit of help. Apparently my actuator for the lock on my left rear door is broken (locks, but will not unlock) so I need to replace. Additionally, when I unlock my doors either from the indise switch or the remote it unlocks...locks...and then unlocks. What up? Do I need a new Master switch or primary lock actuator too? Thanks! Mark
1) Instructions on how to replace the rear door actuator.
2) Diagnosis of other locking problem described, with instructions on fixing.
Pretty much sounds like that's your problem. If your comfortable with drilling out pop rivets and have the tools to reinstall them then it's very straight forward especially in the rear door.
If all your doors lock unlock then it's your computer sensing that something isn't closed (your rear door) and trying to cycle the locks to relock it. If you know for sure that your rear door cannot lock then I'd start by replacing that as you'll have no choice not to do it. If the locks still cycle after that then work on diagnosing the other locks.
Any independent mechanic should be able to do it for you although it would be easier if you figured out how to remove the door panel for them by using the search feature.