Troubleshooting For Scanning Image Defect - Brother DCP-7090 Service Manual

4.12 Troubleshooting for Scanning Image Defect

4.12.1Defect examples
Light
(2-108)
Vertical streaks
(2-111)
4.12.2Troubleshooting according to image defect
 Light
Step
1
2
3
Faulty registration
(2-109)
White streaks
(2-111)
<User Check>
• Check that the contrast setting is not too light.
• Clean the scanner glass or first side/second side scanner glass strip.
• Clean the document hold.
Cause
Incorrect white level
correction data
First or second side CIS unit
failure
Main PCB failure
Dark
(2-109)
Partially shaded
(2-112)
Fig. 2-24
Execute "Acquire white level data
code 55)".
Replace the first or second side CIS unit.
Replace the main PCB ASSY.
2-108
Completely blank All black
(2-110) (2-110)
Fully tinged
(2-112)
Remedy
(Function
Confidential