HP 4000, 4050 manual Blank Possible Cause Action, Voltage

Table 7-12. Blank Page

Possible Cause	Action
No Toner is available	Remove sealing tape or replace the Toner
for print.	Cartridge.
Defective laser	Check the laser shutter for free operation when
shutter.	inserting the Toner Cartridge.
Toner Cartridge Guide	Make sure the guide is installed properly above the
damaged, improperly	Toner Cartridge.
positioned, or missing.
No Transfer Roller	Without Transfer Roller voltage, Toner cannot be
voltage.	attracted from the surface of the Drum to the
	paper. Perform the Half Self Test Functional Check
	(page 7-74) to check all other electrophotographic
	processes. Replace the Transfer Roller if
	necessary.
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	With no ground path the Drum cannot discharge.
Path.	The negative charge on the Drum repels Toner,
	and leaves a white page with bubble print.
	1. Check the Drum Ground Spring and connect it
	as shown on page 6-44.
	2. Replace the Engine Controller Board.
Defective laser	Low-level signals exchanged between the Laser
Scanner Cable	Scanner Assembly and the Engine Controller
Assembly.	Board may be affecting laser output. Replace the
	Laser Scanner Cable Assembly.

Troubleshooting the Printing System 7-59