Measurement And Adjustment; Test Print; Test; Adjustment Of Laser Exposure System - Canon LBP5050 Series Service Manual

5.1 MEASUREMENT AND ADJUSTMENT

5.1.1 Test Print

5.1.1.1 Test Pages
LBP5050N / LBP5050
Printing test pages helps determine if the printer engine and main contoroller
are functioning.
There are two types of test pages: engine-test page and main contoroller-test
page. Print a test page to make sure theprinter engine or the main controller
is functioning.
1) Open the front door and the rear cover unit and then turn the printer on.
2) Close the front door and the rear cover unit within 10 seconds.
3) The engine-test page should have a series of horizontal lines as shown be-
low.

5.1.2 Adjustment of Laser Exposure System

5.1.2.1 After Replacing the laser scanner unit

LBP5050N / LBP5050
When replacing the laser unit, enter the value described on the label included
in the scanner unit into the following service mode.
After entry, put the label [2] inside the right cover [1].
[2]
How to transit to the service mode
1. After the power ON, display the printer driver screen.
2. Change the display from the driver screen to status window.
F-5-1
[1]
F-5-2
3. Enter the password "*28*" with keyboards.
4. Select: Option menu > Service mode > Service parts replacement > Scan-
ner unit replace settings from the status window.
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5.1.3 Adjustment of Electrical Components

5.1.3.1 After Replacing the DC controller PCB

LBP5050N / LBP5050
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The information in the NVRAM on the DC controller PCB is saved as back-
up data in the NVRAM on the main controller PCB.
Executing Printer Setting Restoration in service mode recovers the backup
data in the NVRAM on the DC controller PCB.
When replacing the DC controller PCB, execute recovery of backup data,
color displacement correction, and calibration in service mode.
1) Execute Option Menu > Service Mode > Printer Information settings >
Printer Setting Restoration.
After executing the printer recovery setting, wait completion of the
processing for approx. 15 sec.
2) Turn off/on the power supply of the host machine.
3) Start the Status window.
4) Execute Option Menu > Utility > Out-of-Register Colors Correction.
5) Execute Option Menu > Utility > Calibration.

5.1.3.2 After Replacing the Main Controller PCB

LBP5050N / LBP5050
The settings and management data of host machine is saved in the NVRAM
(IC2S) of the main controller PCB. When replacing the main controller PCB,
be sure to move the NVRAM from the old PCB and to the new PCB.
After moving the NVRAM, execute color displacement correction and cali-
bration.
1) Turn on the power supply of the host machine.
2) Start the Status window.
3) Execute Option Menu > Utility > Out-of-Register Colors Correction in the
status window.
4) Execute Option Menu > Utility > Calibration in the status window.
Chapter 5
F-5-3
T-5-1
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5-1