First at all, after replacing the corona or the wires on a canon box, do not forget to reset the counters in service mode, otherwise the mashine wont use the correct corona currents.
second: turn the trans/sep corona 180 degrees and turn the transfer wire screws 1,5 turn counterclockwise, the two sep wires 1 turn clockwise. After that, reinstall. This will increase the transfer performance and reduce toner repulsion due to sep current
Hope this helps
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