Ken,

There can be multiple issues to cause this. I guess this lift runs on propane. First, make sure the coupling for the tank is completely seated and that the seals are not damaged, tank is full of propane. Have found LP tank full of water. Look at the wires for the LP lock off. These could be loose or worn. There may be an issue with the ECU. Two signals for crank then run. Also, the LP converter will open initially for key on, then shut down, open again once the starter is engaged. Any codes showing on the display?