Just another thought, it may be that your Vane Readers have moved. 1/4 or 1/2 inch is a big deal.If you put the car at the floor on Inspection from the car top. Your Readers should be equal distance apart on the Vane. If they aren't, set them at every floor and then do a learn run. Also the Readers have to be exactly the proper distance apart. I forget the number offhand. My Brain Cells are waning.