Sharp AR-810 Imager, Service Handbook

Page: 288 / 350

AR-651/810 TROUBLESHOOTING 5 - 138
Defective area Step Check Items Prescription Remarks
Developer material/ 1 Using the specified developer material, Use the specified developer material,
Toner/Photoconductive toner and photoconductive drum? toner and photoconductive drum.
drum 2 Have the developer material and the Replace the developer material and
photoconductive drum reached their PM life? photoconductive drum.
3 Is there any film forming on the Clean or replace the drum.
photoconductive drum?
Toner empty 4 Is the toner supply symbol lighting? Replace the toner cartridge.
5 Is the toner cartridge installed properly? Check the installation state of the
toner cartridge.
6 Is the performance of the toner motor normal? Check the performance of the toner motor.
7 Is the toner cartridge normal? Check the toner cartridge.
Replace if it is not normal.
Developer unit 8 Is the developer unit installed Check the installation state of the
properly? developer unit.
9 Is the pushing mechanism of the Check the mechanism.
developer sleeve performing?
Main charger output 10 Is the setting value proper? If the setting value is out of
Is the main charger output normal? specification, adjust it.
If the output is not normal, check
the circuits. (Note 1)
Developer bias output 11 Is the setting value proper? If the setting value is out of
Is the developer bias output normal? specification, adjust it.
If the output is not normal, check
the circuits. (Note 1)
Decreasing toner density 12 Is the performance of the auto-toner Check the performance of the auto-toner
sensor control normal? sensor.
13 Is the toner density low? Correct the toner density.
(Note 2: See ‘Toner density
correcting method’.)
Image quality sensor/ 14 Are the image quality sensor and the Check the performance of the image
Surface potential sensor surface potential sensor normal? quality sensor and the surface potential
sensor. (See the trouble shooting related
with the image quality control.)
Main charger 15 Is the main charger dirty? Clean or replace it.
Note 1:
If the output from the main charger or the developer bias is abnormal, replace the high-voltage transformer with a new one and
output the chart again. If the output stays abnormal, check if the harness connecting the LGC board and high-voltage
transformer is open-circuited, if the power supply is normal and if the main charger wire is dirty.
Note 2:
Toner density correcting method
Change the setting value ‘Toner density life correction setting (08-414)’ (6 is the default setting.)
3: Appox. 1.5% lower than the current value 7: Appox. 0.3% higher than the current value
4: Appox. 0.8% lower than the current value 0: Appox. 0.5% higher than the current value
5: Appox. 0.3% lower than the current value 1: Appox. 0.8% higher than the current value
6: The current value (Default setting) 2: Appox. 1.5% 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. Therefore 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.