Brother Facsimile Equipment MFC7420 - Manual (Page 232)

Confidential 9 - 4 4
I-19 Hollow print
User Check
(1) Check the paper used meets the recommended paper specifications.
(2) Select the ‘Thick paper mode’ in the printer driver, or use thinner paper
than you are currently using.
(3) Check the printer’s environment, conditions such as high humidity may
cause this situation to occur.
Possible cause Step Check Result Remedy
Yes Recommend to use the specified
types of paper. Print paper 1 Is thick paper of more than
43lb being used or
extremely rough surface
paper?
No Refer and compare with [4] Image
defect
I-15.
I-20 Downward fogging of solid black
Possible cause Step Check Result Remedy
Toner
cartridge
failure 1 Is the problem solved after
replacing the toner
cartridge? Yes Replace the toner cartridge.
High-voltage
power supply
PCB failure 2 Is the problem solved after
replacing the high-voltage
power supply PCB? Yes Replace the high-voltage power
supply PCB.