This is the 1st time in years of doing electrical/heating/cooling that I have been stumped. I recently bought a Coleman Spectrum Model 208 hot tub. You can wire it 240 or 110. I wired it 240 through a GFCI diconnect then into the main panel. There is 2 lights on the control panel of the hot tub that have to be on in order for the hot tub to be in normal operation. It states if the left light is off and right is on there is a polarity wiring issue. It then says if the left light is on and right is off the white neutral wire is not connected. If both lights are off there is no power to the unit. When turning on it shows the right light off stating the white wire is not hooked up. I vaildated the wiring in the control panel to the scematics and validated the breaker box as well. Neutral is hooked up through the GFCI, to the Neutral bus bar, and to the neutral bus in the main panel. Any idea's what else would cause this fault.