All good advice on keeping the batteries up to charge.
Regarding the "interface cable". If your rig is like mine, you have Bigfoot levelers with the control panel located on the entry step wall. If the lights are blinking on the control panel, you will need to rest the system. To do this, you remove the 4 screws holding the control panel and pull the panel out from the wall. On the back of the panel, you will see the "interface cable" that plugs into the back of the panel. Unplug the cable, wait a couple of minutes, plug the cable back in. You lights on the control panel should not be blinking anymore. Replace the panel.
You will find a lot of help on the
Bigfoot Support Page.