2000 G3500 cargo van. Drivers side door won't unlock with the key or from the inside (mechanical) lock unlock lever. Something is getting jammed, the key will not turn all the way and the inside lever resists being slid to the unlock position.

This started years ago, maybe 1 or 2 times in a year. I had found that if I gave the lock area a gentle hit with the side of my fist it would suddenly work perfect again. Years later I seldom drive it and this lock is getting stuck more often and is not opening as easily and the gentle hit is now getting to be a hard hit and it may take 50 hits to open. I can enter from the passenger side but still can't unlock it from the inside.

Today it happened and after 15 minutes of beating on the door it suddenly unlocked when I lifted the lever. I removed the door panel and can see the linkage from the key lock and from the indoor lock working properly, but I couldn't get it to jamb unless I slammed the door closed. With the door closed it about impossible to see the linkage. So I keep trying to get it to jamb with the door open. I'm hoping I don't have to drill out the RIVETS and remove the window assembly just to see better. Anyone see or hear of this problem?

Thanks,
Solkim

 

There is a safety on the door lock. If the door is open, then you cant lock it up. I'm not really sure, but there is a button on the door, lights the interior light when the door is open. I think, if you put some tape on there, so that it remains pressed in, then you can temper the locks with the door open.
My guess is , that you might be able to cure it with some Graphit. Just spray it on all the moving parts.

 

Put a screwdriver in the latch to simulate a closed door then play with the locks to see if you can get them to act up

 

There is no safety on my door locks, they are 100% mechanical not electric.

 

Great idea! So simple. After all these years I never thought of that when repairing other door latch problems. I'll give it a try.

Solkim