Check the firmware Sharp released a version to fix just this issue.
Complete Engine Firmware
Models MXC311, MXC401, DXC311, DXC401
Release Type Production Control ROM ID D04
Release Date October 2010 File Name CFRW_MAINsEFS_101122a.sfu
Reason to change: (correction of error described below)
1. Changing the 2nd transfer separator control sequence could stop causing an L4
Reason to change: (specification change)
2. A service mode to force toner onto the 1st transfer belt and to prevent the 1st transfer blade from being
reversed has been added to the engine software SW (Sim55‐1).
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