Originally Posted by luckyfam4
My automatic tongue jack has stopped working except when it is connected to the truck AND the truck engine is running, otherwise it does not function. Anyone seen this? I have swapped out the fuse but still have the same issue,
This was just discussed recently. Sounds like a bad ground connection - when you're connected to your TV the jack is getting a ground from the truck. Look for your chassis ground on the trailer, fairly near the battery. Also check the wiring of the jack to make sure it's tight and you've got a good ground there.
There are other possibilities, like a blown fuse. Anything else giving you trouble? If you have other electrical issues in the 12v system that would give us clues. Heck, you could even have a dead battery.