Battery won’t power our Shamrock 19 jack lift.

[cavie]

If the jack works when hooked to shore power there is no problem with the jack. Plane and simple. It works or it don't.

If it does not work on battery alone then the problem is with the battery and/or it's connections. Plane and simple. Anything less than 12 volts on the battery it's dead as to being able to run the jack. It will light lights or run a water pump but not a jack. Charge the battery and have it load tested with an old fashion restive load tester. Not a fancy computer read out style. Just because the battery is new does not mean it is good! Clean all connections.

[Chuck_S]

It's gotta be the battery.

All 12vDC circuits are tied together. If the jack works on shore power it should work on battery power if the battery is fully charged. It should also work connected to the tow vehicle and that vehicle is running (my Fords switch that wire with the ignition).

I can't see how this won't work unless your trailer battery is the same one your electric start lawn mower or motorcycle uses. These tiny batteries are all that's needed for the emergency brake disconnect switch.

-- Chuck

[Wolverine 1945]

While on a trip out west last fall our Tong Jack decided not to work !!!
Found a Fuse under the battery Box, it looked good so I put it back in, Jack then worked for a couple of days, @ our next stop, in IA one of the Park Rangers help me trace the wires, as far as we could, so we decided it was dead,
I forgot to mention the TT is a 2020 Flagstaff,
The ranger then hit top of the Jack housing with his hand, It then started working again, as I thought there must be a short inside !!!
When we got home our dealer came out to look @ the Jack and our Microwave, because its door was not opening when we pushed the button, they ordered a new Jack & Microwave, ??? and changed them !!!

So the problem with the JACK was a loose connection, in the Housing !!!