This sounds similar to the classic "Short in the door wiring" symptom. 

To diagnose, follow the wires from the door to the connectors under the dash. 
Unhook the driver's door, then see if they work normally (except for the door you unhooked.) Then reconnect and unhook the passenger side and test again. 
The side that causes the door locks to work normally again is the side with the broken wire in the door. 

I see you think the problem is the actuator, but I would also make sure you check the wires. 
If the wires are broken, it will not sense that you are opening the lock and will continue to try to cycle the lock when you try to open the lock. 

Todd 

----- Original Message -----

From: "Neil N" <musomuso@GMAIL.COM> 
To: vanagon@GERRY.VANAGON.COM 
Sent: Wednesday, September 23, 2015 1:24:26 PM 
Subject: Power Door Locks: Key Won't Turn Pass. Side Door Lock. 

Hi all. 

Did a quick search but didn't find what I was looking for. 

Symptoms: passenger side front door power lock won't turn with key. 
Understandably so, turning key in driver side door causes locks to unlock, 
then lock. 

This has happened before. I've cleaned and lubed the pass. side front door 
actuator twice now. After each service, that lock worked fine then 
eventually get stuck. 

I don't think this is possible, but can the actuator wheel-sliding bit be 
re-assembled 180º out of phase, still allow actuator to work fine but then 
eventually cause it to bind? Or, is the actuator just worn out? Or, is the 
issue limited to the rod and how it interfaces with the actuator? Parts 
need more lube at specific areas? 

Some pics of the part from my first "service" 
http://tinyurl.com/o5tk24l 
or https://picasaweb.google.com/musomuso/New1988Westy#6121145675944390754 

As nice an option as it is, I'm tempted to just delete the Central locking 
system and go purely mechanical. 

Thanks, 

-- 
Neil n 

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