5-14 Phaser 7750 Printer Service Manual
Blank Prints
The entire image area is blank. 
1. Generate a 100% “Solid Fill Test” print 
from the front panel.
2. Open the door in the middle of the print 
job. Is there toner on the Accumulator 
Belt?
3. Enter service diagnostics and test the 
shutter motor. Does the laser shutter motor 
work properly? Remove an imaging unit 
and see if the shutter opens and closes 
freely.
4. Inspect the wiring harness for loose or 
disconnected wiring connectors; check 
connectors P400 and P401 at the engine 
control board.
5. Print the “Engine Test Prints”. If the test prints are free from defects, replace the 
Image processor Board. If the test prints show defects, replace the engine control 
board.