Happijack Intermittant Problem

Happijack new motors design changed wire enters under gear housing.

Old design wires entered side of round motor housing
Clearly there was a design issue
My jacks are over six years old with thousands of miles ,never had to grease lead screw
They manually crank up and down with no effort.

I had one go bad and I now cover the heads with triple gang electrical box vapour barrier gaskets. Looks kinda ghetto but it's cheap and haven't had any more problems.

As links to the HappiJac PDF files listed in the TCU thread were not working I uploaded again to google-
can be downloaded from

https://drive.google.com/drive/folders/1dfkxKiCIuDGdBL8Db6SK78Maa9h1ZrbQ?usp=sharing

I have had two of these motors leak and die as shown above. I have tried caulk around all the seams. I have also tried covering the motors and tops of the jacks with plastic freezer bags. Happijack clearly has a design issue.

Where is the entry point for water?

Had two HappiJack motors die ,started with same symptoms as yours.
inside of electric motor full of water ,bad bad design.

If you have a wired remote, it could be a bad wire in the remote cable. Try another cable. A plain telephone cable works.

Like you, I have also had puzzling intermittent problems with the Happijacks. I recommend you read the sticky at http://www.rv.net/forum/index.cfm/fuseaction/thread/tid/22881036.cfm
I used this as my guide in totally disassembling the Happijacks, cleaning and lubricating. Water gets down inside and grease gets stiff on the screw. It is possible to take the motor unit off the top without removing the jack from the camper. I've done that and added oil (better that than water). If the problem is electrical, depending on how your camper is built it may have an ethernet connector where the Happijack controller cable passes thru to the outside. I've replaced mine 3 times in 10 years because of corrosion.

My guess is the motor itself if slapping fixes things.

Have a look at the very top of this forum under Truck Camper University. Quite a ways down is some useful information on taking apart the jacks.