I have an 88 XJ6 that has suddenly developed a problem with the rear door locks. When I insert and turn the key to unlock the doors the rear locks pop up but immediatly pop back down. This also accurs using the button on the dash. I understand theres a couple of different sources, I guess I'm looking for the most common. Thanks

 

You need to lube the latches. The actuators can only apply so much force and sometimes that is not enough to overcome neglected latches.

Most of the time lubricating works but sometimes they need replacement if severely corroded or damaged/broken.

bob gauff