Toner Density Too High - Ricoh A151 Field Service Manual

1.12 TONER DENSITY TOO HIGH

- Problem -
1. Dirty background appears on the copy.
2. The image density of black solid areas is too high.
3. Toner has built up on the endblock covers of the TC/SC corona unit and
also on the upper cover of the development unit.
- Possible Causes -
1. The light intensity of the exposure lamp is too high.
2. The toner supply clutch keeps on turning continuously.
3. The copier is in fixed toner supply mode.
4. The main board is defective.
5. The ID sensor bias voltage (modules) is too low.
6. The charge corona current is too low.
7. The ID sensor grid voltage is too low.
- Action -
Has an ID sensor abnormal condition occurred?
No Yes
See the ID Sensor Abnormal Condition section.
Clean the optics section and the area around the drum. Clear the V
rection with SP95. Make a few sky shot copies and then readjust the light
intensity and the ADS voltage.
Does the toner supply clutch turn even though there is sufficient toner in
the development unit?
No Yes
Check the voltage at CN110-1 on the main board.
24 volts 0 volts
Replace the toner supply clutch.
No
Is the copier in fixed mode?
No Yes
A151/A152
Replace the main board.
6-16
cor-
L
FSM