Samsung ML-1665 Service Manual page 75

4) Black/White Spot
Description : 1. Dark or blurry spots occur periodically in the printing
2. White spots occur periodically in the printing
the rollers in the Developer may be conta-
minated with foreign matte or paper particles.
of 62.9mm, or black spots occur elsewhere,
partially broken, the transfer voltage is
Service Manual
Alignment and Troubleshooting
1. If dark or blurry
black spots occur periodically,
(Charge roller : 26.7mm interval
OPC drum : 62.9mm interval)
2. If faded areas or voids
occur in a black image at intervals
the OPC drum surface is
damaged.
3. If a black image is
abnormal or the transfer roller's
life has expired.
Run the Self-test 2 or 3 times.
In case of 62.9mm interval
unremovable in 1, cleanly remove
foreign substances stuck on the OPC
location equivalent to black spots and
white spots with a dry duster.
1. The transfer roller guarantees
30,000 sheets printing. If the
roller's life is expired, replace it.
2. In case of 39.2 mm interval
unremovable in 1, take measures
as to replace the develop-er
cartridge and try to print out.
5. Clean the inside of the set against
the paper particles and foreign
matter in order not to cause the
trouble.
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