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Symptom: Horizontal black stripes
1. Is the Call Service
indicator lit?
Replace the LD unit or FCU.
Go to step 2.
2. Check that the master unit is installed properly and correctly grounded.
Change the master unit if it is damaged.
If the problem only occurs in copy mode, the xenon lamp may be flickering: change the
lamp, driver, or FCU.
If the problem remains, go to step 3.
3. Does the development
bias terminal stay at a
constant voltage
(about -530 Vdc)?
Go to step 6.
Go to step 4. Do not adjust
the variable resistors on the
power pack.
4. Does the FCU output the
power and bias trigger
signal to the power pack?
Clean the area around the
bias terminal. Go to step 5.
Change the FCU.
5. Does the problem go
away if you change the
power pack?
Finished.
Clean the development
roller. Go to step 6.
6. Check that the toner metering blade is screwed in securely.
Symptom: White spots in black areas
Check
Action if Yes
Action if No
Clean the development roller (soft cloth and alcohol).
Clean the corona wires.
If the problem cannot be solved, change the development unit, master, or power pack.
Symptom: Data missing at the leading edge
Check
Action if Yes
Action if No
1. Does the problem only
occur during copying?
Go to step 2.
Go to step 3.
2. Check that the scan line sensor is in the correct position.
Try changing the FCU.
3. Is the correct type of copy paper being used, and is it curled at the leading edge?
Check for dust on the rollers in the paper feed path.
Lower cassette: Is the registration mechanism working correctly?
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TROUBLESHOOTING
1st August, 1994
COPY QUALITY TROUBLESHOOTING
6-9