My 87 300D's central locking is driving me crazy, literally, when I got the car it worked but not well. It had a few leaks so I fixed all by changing the drvs door, trunk and fuel flap lock actuators. Worked perfectly so I added the keyless system and again it worked perfectly for 2 or so months. Then yesterday driving along it locks on it's own for no particular reason. I tried it a few times and always the same, although the time it would take varied. I put it in the shop thinking something frozen and tried it a few times and then it stayed unlocked. This morning it doesn't work at all so I pulled the seat and checked it out. There appears to be no 12v at the connector. Fuse is good, no problem there, no leaks at all, pump will run if I connect 12v to it but it will do the same thing, the keyless will work as it should but when I unlock it it now will immediately lock. I tried it several times, the drvs key will not lock or unlock (with the pump) and it always did. So I am baffled, it makes no sense unless it is the drvs door actuator stuck in the unlock position but that still doesn't explain no 12v at the pump. I vacuum tested, no leaks.. Does anybody have any idea what is going on with it? It seems so simple but apparently not so much.

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1987 300 TDT
1990 300 SEL