I searched my posts for disassembly and reassembly of door lock stuff:
Look here for remote stuff:
http://forums.justcommodores.com.au/vn-vp-holden-commodore-1988-1993/147119-remote-vp-commodore.html
and here's how to play with your locks: I cut and pasted this so use whats right for you.
I've posted this a few times for central locking problems, the disassembly and reassembly will apply to your problem, just ignore what don't apply to you.
What usually goes wrong with mechanical locks is wear and lack of lubrication, particularly in the tumbler area (where the key goes) This can be disassembled (keep the pins in strict order) and cleaned with metho or you can spray it intact with a cleaner that contains a dry lube such as for fishing reels and zips. You don't want to use sticky/greasy lubes on the tumblers as the pins need to move freely. Sticking pins is usually the mechanical problem.
To disassemble door: door trims off (remove plugs covering screws in arm rest, screw under door handle, pop out lock inner orange bit, pop trim loose from bottom and once clippy things are loose push whole trim up out of window channel) and cut inner plastic shield over lock area on 3 sides, (big enough to get your hand in) peel it back undo 3 star drive screws from end of door (allen key works ok) unplug solenoidy thing, unclip linkage, remove lock assembly and clean all linkages and moving parts. Solenoidy thing attaches with a couple of screws, clean plug and connector with metho if they're dirty, plug solenoid in before reassembly and test. Sometimes this works real well, sometimes the solenoid man is tired and it's time for a trip to the wreckers. Unfortunately you may not be able to say which before it's been tested for a few weeks.... After a bit of practice it doesn't take more than 15-20 minutes per door. First door probably more like an hour. take the opportunity to clean window bottom where you can't usually reach and vac fuzzy trim edge that sits against window. Getting trims back on, push into window channel first, leave trim tilted out while you get clippy men lined up and start pushing in from top and line up lower down as you go. You'll have to lie on the ground looking up into the gap to line up the clips. have fun!
