Post your problem (MX4501) in the Sharp thread, you'll probably get more responses. The trouble is most likely a problem with the primary transfer belt lift. Run TC 6-3 to check belt; it should run between "Black", "Color", and "Free".
You should be able to hear the rotation of the cam as it executes. Good luck!
You should be able to hear the rotation of the cam as it executes. Good luck!