Jack goes down but not up
Recently my tongue jack quit going down but would still go up. I called the folks at Barker and without hesitation they said it was the toggle switch. They were nice enough to send a new switch at no cost. I just installed the new switch and presto everything works! Plus no trips to the hardware store (very rare).
In the mean time, a 7/16 socket and ratchet did a pretty good job of raising the trailer. Keep in mind that the electric disconnect switch doesn't shut off the jack but you can disconnect the in-line fuse.
I thought this might be helpful to others.