Volvo 850 tail gate lock

I use the ignition key. The internal lever needs to be fixed. That is a safety item. Here are a few old posts:

"I've seen something similar once.  Removing the mechanism showed that the rivets holding the two halves of the lock together had loosened up. Banging them a few times with a hammer and heavy punch tightened the rivets and restored proper function.  I hope this works for you." Mike F. Thornhill (near Toronto), Ont.

"My tailgate lock was dodgy when I got it. Couldn't unlock it electrically, and could only sometimes unlock it with the key. The electric device made sounds, just didn't unlock the door. I pulled the upholstered panel off and found this inside:

 The problem was that rod going toward the top left corner. It threads into the white piece in the middle and just needed to be adjusted a bit to keep the other parts from jamming. I don't remember the exact operation of the thing any more; it took a little examining at the time to figure out which piece was supposed to do what, but it wasn't rocket surgery."Ernest Scribbler