With no shorts found the controller was wired up. Key-on is now clean - no blinking dash, no codes. Lift functions & mast hydraulics are normal. Truck also moves forward & back (briefly).

The battery definitely needs attention. After key start, moving forward or back the parking brakes come on right away. I'm thinking the traction current draw overwhelms the battery. Cycling the key resets a clean start.

The battery condition barely reaches the green range after charging overnight. A brief amount of running lowers it to the red/yellow area of the display.

Is a recon battery a good way to go? Thanks for any ideas - and for reading this far.