Canon PC980 Service Manual - Page 307

CHAPTER 11 TROUBLESHOOTING 2. Adjusting the Intensity of the Scanning Lamp Adjust the intensity of the scanning lamp if you have replaced any of the following: • DC controller PCB • Composite power supply PCB (See p.11-41.) • Scanning lamp Caution: If you have performed this adjustment, you must always perform AE adjustment. Making Adjustments 1) Set a cartridge in the machine. 2) Set the density correction switch (SW101) to its middle index. SW101 Figure 11-263 3) Turn off the AE mechanism, and set the copy density adjusting lever on the control panel to its middle index. 4) Place the Test Sheet on the copyboard, and make a copy. 5) Turn VR107 on the DC controller PCB gradually until gray scale No. 9 is barely visible. VR107 J131 J101 J102 J101 J130 J114 J102 VR104VR105VR106 VR107 VR103VR102 J107 J103 J104 J105 Figure 11-264 J109 J106 VR107 and Copy Density Direction of VR107 Clockwise Counterclockwise Copy density Lighter Darker Table 11-207 11-42 COPYRIGHT © 1999 CANON INC. CANON PC800s/900s REV.0 AUG. 1999 PRINTED IN JAPAN (IMPRIME AU JAPON)