I know the locks on my 83 300D aren't working correctly but how are they supposed to work? Is there a button somewhere for lock/unlock? Do they all automatically unlock when I unlock a front door with the key? Also, my back passenger door seems to be frozen. It wont open from the inside or out. It started out by being stuck with the door not closed properly. I tried giving it a little push to close it but nothing. I went for the door handle to open it and slam it shut and...nothing. Even though the door was unlocked it wouldn't open. The same happens from the inside. Does something need to be replaced or is this related to the locks not working correctly?

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1983 300D TurboDiesel