EN
Troubleshooting the Printing System
7-55
DC Controller PCA is
defective. The DC
Controller supplies the
proper voltage to the
High Voltage Power
Supply PCA.
Replace the DC Controller PCA.
No Developing Bias. 1. Clean the High Voltage Power Supply contacts.
With no Developing Bias charge, toner is not
attracted to the drum.
2. Replace the Engine Controller Board.
No drum ground path. With no ground path the drum cannot discharge. The
negative charge on the drum repels toner, and
leaves a white page with bubble print.
1. Check the drum ground.
2. Replace the Engine Controller Board.
Defective Laser
Scanner Cable
Assembly.
Low-level signals exchanged between the Laser
Scanner Assembly and the Engine Controller Board
may be affecting laser output. Replace the Laser
Scanner Cable Assembly.
Table 7-12. Blank Spots
Possible Cause Action
Paper does not meet
printer specifications
or is stored
improperly.
1. Print a few more pages to see if the problem
corrects itself.
2. Turn over the stack of paper in the tray. Also try
rotating the paper 180°.
3. Check the paper (or other print media) type and
quality. Replace the paper, and advise the customer
to use the recommended paper and store it properly.
Defective Toner
Cartridge.
Replace the Toner Cartridge.
Table 7-11. Blank Page (continued)
Possible Cause Action
