On an 83 380SL, I have a problem with my door locks. The car came with two keys (appear identical). They start the car, and work in the passenger (RH) door. The RH door will unlock the entire care if the LH door is locked manually, but it won't lock the car. The RH door will activate the automatic lock/unlock Neither key will work in the trunk lock or the driver (LH) door; they just do not turn.
The car is new to me, but I have no reason to think the locks have been changed.
I assume it has something to do with the vacuum system, but I cannot comprehend what that might be.
Suggestion on how to go about fixing this would be appreciated. Thanks in advance.
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