Electric Jack Only Works When Connected to Tow Vehicle

Published 08/17/2018

Question:

I forgot to mention that the trailer battery is fully charged, so this isnt the problem.

asked by: Kim

Expert Reply:

The problem you have with the Electric Jack w/ Footplate part # EJ-3520-BBX is likely due to a dead battery. The reason it will only work when connected to the tow vehicle is because the tow vehicle is using the 7-way trailer connector to provide a charge to the trailer battery. The trailer battery is likely dead since the jack only works when hooked up to the tow vehicle which in this case is the battery charger. I recommend checking the trailer battery to ensure it is fully charged.

expert reply by: Conner L

Kim

8/17/2018

I forgot to mention that the trailer battery is fully charged, so this isnt the problem.

Conner L.

8/17/2018

When you say connected to the truck do you mean via trailer wiring or hitch ball to coupler? If you are referring to the hitch ball and coupler connection then the issue is likely a ground. What you will need to do is remove the jack from the mounting plate, sand down the surface, and then sandwich star washers between the jack and mounting plate on each bolt hole while bolting the jack back down. This should fix the issue you are having with your jack.