Brother DCP-7090 Service Manual page 152

 Partially shaded
<User Check>
Step
1 Dirt inside of scanner glass
2 Deformed document sponge
 Fully tinged
Step
Incorrect white level
1
correction data
First or second side CIS unit
2
failure
3 Main PCB failure
• Clean the scanner glass.
Cause
<User Check>
• Clean the scanner glass or first side/second side
scanner glass strip.
Cause
2-112
Remedy
Clean the inside of scanner glass.
Replace the document scanner unit.
Remedy
Execute "Acquire white level data
code 55)".
Replace the first or second side CIS unit.
Replace the main PCB ASSY.
(Function
Confidential