Toshiba e-STUDIO520 Service Handbook page 505

Defective area
Main charger
Main charger output
Developer bias output
Transfer belt
Note: Note:
1. Toner density correcting method
Change the setting value 'Toner density life correction setting (08-414)' (6 is the default setting.)
0: Appox. 0.75% lower than the current value
1: Appox. 0.50% lower than the current value
2: Appox. 0.25% lower than the current value
3: The current value (Default setting)
4: Appox. 0.15% higher than the current value
5: Appox. 0.25% higher than the current value
6: Appox. 0.50% higher than the current value
7: Appox. 0.75% higher than the current value
<Caution for correction>
When increasing or decreasing the toner density too much, the image may become poor or the
life of developer material, cleaner, photoconductive drum and fuser unit, etc. may shorten. There-
fore it is not recommended to correct (to shift) the toner density basically. If it is shifted, make
sure that the image may be improper in a few minutes after shifting.
© 2005 - 2007 TOSHIBA TEC CORPORATION All rights reserved
Step Check items
12 Is there any foreign object on the
charger?
13 Is the charger dirty or deformed?
14 Is the setting value proper?
Is the main charger output normal?
15 Is the setting value proper?
Is the developer bias output normal?
16 Is there any foreign object or fiber,
etc. on the belt surface?
5 - 143
Prescription
Remove it.
Clean or replace the main charger
wire and grid.
Replace the high-voltage transformer
with a new one and print out a test
chart.
If any abnormal image appears,
check the harness connection
between the LGC board and the
high-voltage transformer, power sup-
ply and stain on the main charger
wire.
Replace the high-voltage transformer
with a new one and print out a test
chart.
If any abnormal image appears,
check the harness connection
between the LGC board and the
high-voltage transformer, power sup-
ply and stain on the main charger
wire.
Remove it.
e-STUDIO520/523/600/603/720/723/850/853
TROUBLESHOOTING
5