Canon iR8500 Service Manual page 35

CONTENTS
2.4.11 Position of the Delivery
Flapper Solenoid (SL3) ..... 6-29
2.4.12 Position of the Fixing Feeding
Unit Locking Solenoid
(SL4) .................................. 6-30
2.4.13 Adjusting the Position for
the Multifeeder Pickup Latch
Solenoid (SL6) .................. 6-31
2.4.14 Position of the Deck (right)
Pickup Solenoid (SL7) ...... 6-32
2.4.15 Position of the Deck (left)
Pickup Solenoid (SL8) ...... 6-33
2.4.16 Position for the Cassette 3/4
Pickup Solenoid
(SL9/10) ............................. 6-34
2.4.17 Position of the Side Paper
Deck Pickup Roller
Releasing Solenoid ............ 6-35
2.4.18 Attaching the Timing Belt for
the Manual Feed Tray
Assembly Side Guide ....... 6-35
2.4.19 Attaching
the Drive Belts ................... 6-36
2.5 Fixing System .......................... 6-37
2.5.1 Points to Note
When Mounting the Fixing
Heater ................................. 6-37
2.5.2 Adjusting the Lower Roller
Pressure (nip width) ........... 6-38
2.6 Laser Exposure System ............ 6-39
2.6.1 Replacing the Laser Unit ......... 6-39
2.6.2 Checking the Laser Power ....... 6-40
2.7 Items Related to Electrical
Components ............................. 6-43
2.7.1 Electrical Components
Requiring Work After
Replacement ...................... 6-43
2.7.2 Points to Note when
Replacing the CCD Unit .... 6-43
2.7.3 When Replacing the Reader
Controller PCB
(iR8500) ............................. 6-45
xviii
2.7.4 When Replacing the Reder
controller PCB
(iR7200) ............................. 6-46
2.7.5 Replacing the Main
Controller PCB .................. 6-47
2.7.6 Replacing the HDD Unit ... 6-47
2.7.7 Replacing the DC Controller
PCB .................................... 6-48
2.7.8 After Replacing the
High-Voltage DC PCB ....... 6-49
2.7.9 When Replacing the Laser
Unit .................................... 6-50
2.7.10 Replacing the Potential
Sensor/Potential Control
PCB .................................... 6-50
2.7.11 Checking the Surface
Potential Control System ... 6-54
2.8 Conversion Table for
the Potential Control System ... 6-60
2.9 Checking the Environment
Sensor ....................................... 6-65
2.10 Checking the Photointerrupters 6-66
3 Troubleshooting Image Faults .......... 6-72
3.1 Making Initial Checks .............. 6-72
3.1.1 Site of Installation .............. 6-72
3.1.2 Checking the Originals
Against Symptoms ............. 6-72
3.1.3 Checking the Copyboard
Cover, Copyboard Glass,
and Standard White Plate
for Dirt and Scratches ........ 6-73
3.1.4 Checking the Charging
Wires .................................. 6-73
3.1.5 Checking the Developing
Assembly ........................... 6-73
3.1.6 Checking the Paper ............ 6-73
3.1.7 Checking the Periodically
Replaced Parts ................... 6-73
3.1.8 Others ................................ 6-73
3.2 Sample Faulty Images .............. 6-76
3.3 Troubleshooting Faulty
Images ...................................... 6-77
3.3.1 The copy is too light
(halftone area) .................... 6-77
REV.1 AUG. 2001