Troubleshooting Trailer Jack that Won't Raise With Just Battery Power

Updated 03/12/2025 | Published 03/03/2025

Question:

My jack will not raise the trailer unless we are plugged into outside power. The battery is fine and all connections have been cleaned. The motor does work on the battery itself but not enough strength to lift. Help.

asked by: Larry

Expert Reply:

Its sounds like the battery has seen better days. Was it always like this or did this happen recently? A battery can sometimes have a high enough voltage to appear good but it doesn't have the amperage to power anything.

expert reply by: Jameson C

Larry

3/12/2025

New battery. All connections checked and cleaned. Same issue.

Jameson C.

3/12/2025

@Larry Does the motor try and work on just the battery? Or does it just not work at all? When it's plugged to outside power does it strain at all or does it work totally normal? If you have a vehicle nearby and a set of jumper cables I would try jumping it to the trailer battery and trying the jack again. This will for sure tell us if the problem is battery related in any way.

Larry

3/12/2025

@JamesonC the motor runs fine but very weak when just on battery. NEW BATTERY. Last thought is power cable from battery to jack?

Jameson C.

3/12/2025

@Larry Well it could be power wire from jack to the battery or even the ground wire. Is it at least 10 gauge wire? If not, I would try that as it sounds like the jack is just not able to get enough power. Does the power or ground wire get warm to the touch when it's in use?