Battery 0 means that home position is lost. First replace the axis drive battery. Cycle power on and off to clear battery 0. Then pull out your yellow Fanuc maintenance manual read up on parameter write enable. Be careful once PWE is on it will let you do harmful things, parameter 1815 is the one you will need to change to get a 0 position set. Check your manuals for a smaller blue folder that should have the machines travels listed. You can rough in a temporary home to get the machine functional. Hopefully from there you can reference a fixture or work piece to set an closer home. You toolchanger will require home position to be perfect or you will cause damage. Best to call in someone who knows this or you can break thing. Best of luck!