Toshiba DP1600 Service Handbook page 188

(6) White banding (at right angles to feeding direction)
Step Cause/Defect area
1 Process unit (developer)
2 Transfer charger unit
3
4
5 Process unit (drum)
6 Fuser unit
7 Gear and roller
8 HVPS (main charger,
transfer charger and
developer bias)
9
1600/2000/2500 TROUBLESHOOTING
Check items
Developing bias terminals (pro-
cess unit) and corresponding ter-
minals (main body) stained?
Transfer charger unit securely in-
stalled?
Transfer charger wire terminals
and corresponding terminals
stained?
Is guide roller stained or rotating
improperly?
Guide roller stained or rotating
improperly? Guide roller shaft
grouded improperly?
Any abnormalities on drum sur-
face?
Toner on heat roller surface?
Scratches on heat roller surface?
Check each gear or roller for pa-
per feed and transport is dam-
aged?
High-voltage output defective?
If problem persists after measures
are applied, or there is no prob-
lem found in above check, follow
procedure described in right col-
umn.
4 - 64
01/11
Measures
Clean terminals.
Re-install transfer charger unit securely.
Clean terminals.
Clean guide roller.
Ground shaft properly.
When guide roller rotates improperly, replace
transfer charger unit.
Replace process unit or drum (SRU type).
Clean heat roller. If problem persists, replace
heat roller.
Replace defective gear or roller.
Adjust output from HVPS, or replace defec-
tive HVPS.
Replace process unit or transfer charger unit.
December 2000 © TOSHIBA TEC