How To Identify Problematic Part - Konica Minolta bizhub C450 Service Manual

Field Service Ver. 1.0 Mar. 2005

18.2 How to identify problematic part

• This chapter is divided into two parts: "Initial Check Items" and "Troubleshooting Proce-
dure by a Particular Image Quality Problem."
• When an image quality problem occurs, first go through the "Initial Check Items" and, if
the cause is yet to be identified, go to "Troubleshooting Procedure by a Particular Image
Quality Problem."
18.2.1 Initial Check Items
A. Initial Check Items 1
• Check first to see if image data is properly transmitted between Scanner and memory,
and between memory and printer.
Enter the Service Mode, select "State Confirmation" → "Mem-
ory/HDD Adj." → "Memory Bus Check," and select and carry out
"Scanner→Memory" and "Memory→PRT" checks.
B. Initial Check Items 2
• Let the machine produce a test print and determine whether the image problem is attrib-
utable to the Scanner or printer system.
Scanner
system
Printer
system
• Evaluation Procedure
Image
Problem
From "Service Mode," select "Test Mode" →
"Halftone Pattern" → "SINGLE" → "HYPER"
Lines,
→ "Gradation" → "C→M→Y→K" → "Density
bands
64," and produce a test print. Is image prob-
lem evident?
Action
Document Scan
CCD Sensor Board PWB-A
Image Processing Board
PWB-C
Copier Board
PWB-CF
LED Drive Board
PWB-LED
Action
18. Image quality problem
Result
OK Initial Check Items 2
☞
NG 364
(action as instructed)
I/F Cable
MFP Control Board
PWB-MFPC
Test Print
Result Cause
YES Printer
☞
NO Scanner
Next Step
C
Next Step
Initial Check Items 3
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