Troubleshooting Image Faults; Making Initial Checks - Canon NP6512 Service Manual

CHAPTER 11 TROUBLESHOOTING
III. TROUBLESHOOTING IMAGE FAULTS
A.

Making Initial Checks

1. Site Environment
Check the site against the following considerations:
a. The voltage of the power source is as rated.
b. The site must not be subject to high temperature or humidity (as near a water faucet, water
boiler, humidifier) or dust. The machine must not be near a source of fire.
c. The site must not be subject to ammonium gas.
d. The machine must not be exposed to direct rays of the sun. (As necessary, instruct the user to
provide curtains.)
e. The site must be well ventilated.
f. The machine must be kept level.
2. Checking the Originals
Check the originals to find out whether the problem in question is caused by the machine or the
originals.
a. The copy density adjusting lever is often best if set to the middle index.
b. Originals with a red tint tend to produce copies with poor contrast; e.g., red sheets.
c. Originals which are diazo copies or with transparency tend to produce copies which can be
mistaken for "foggy" copies.
Originals prepared in pencil tend to produce copies with "light" images.
3. Copyboard Cover and Copyboard Glass
If the copyboard cover or the copyboard glass is soiled, clean it with mild detergent solution or
alcohol; if scratched, replace it.
4. Lens
Check the lens for dirt. If any, clean it with a cotton swab.
5. Checking the Transfer Charging Roller
a. Check the transfer charging roller for dirt or fault (scratches).
6. Feeding Assembly
Check the feeding assembly for dirt. If any dirt is found, clean it with a moist cloth.
7. Copy Paper
a. Is copy paper of a type recommended by Canon?
b. Is copy paper moist?
Try paper fresh out of package.
11-52
COPYRIGHT © 1999 CANON INC. CANON NP6512/6612/7120/7130/7130F REV.0 AUG. 1999 PRINTED IN JAPAN (IMPRIME AU JAPON)