Wanted to add the findings on this one. Turns out there is 12V power on the grey front sensor line that interferes with both the sensor resistors and the entire panel. The dealer traced it and could not find where the 12V's was being added, although it was somewhere between the panel and the bed as the sensor line after the bed did not have the 12V on it, nor as it left the coach and went underneath to the tank. Pull the kitchen cabinets and found the problem with a line for the lights being directly connected to this sensor switch. I never noticed that the 12v light above the sink did not come on. But now that I fixed also.
Just shows how complex the wiring is.
But after all that, I decided to switch out the sensors with a SeeLevel II system. I'll post that in the mods and update forum.