1320C Color Laser Printer - Paper Jam Issue (rollers ? - sensor)

have a dell 1320c (color laser printer). at first the ! was blinking and indicating a "Printer Jam"- error code-071-100. there is no paper anywhere and I suspect a sensor, or roller being the issue. eventually the ! stopped blinking anf now it just shows me a blinking paper tray error. The unit will print from the single slot paper input area, but not from the tray.I have removed the rubber from the tray and cleaned it, no difference. any idea's ??  I also looked at the roller assembly that sits on the bottom of the printer ( I also cleaned that as well ).  Should the rubber part of that roller be 90 degrees vertical facing down, or should it be facing @ 45 degrees when looking at it from the front of the printer ?