Specifications

1.12 TONER DENSITY TOO HIGH
- Phenomenon -
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 cover of the TC/SC corona unit and
also on the upper cover of the development unit.
- Possible Causes -
1. Light intensity of the exposure lamp is too high.
2. Toner supply clutch keeps on turning continuously.
3. Copier is in fixed toner supply mode.
4. Main board defective
5. ID sensor bias voltage (modules) is too low.
6. Charge corona current is too low.
7. 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 around the drum. Make a few sky shot copies
and then readjust the light intensity and the ADS voltage.
Does the toner supply clutch solenoid turn even though there is sufficient
toner in the development unit?
No Yes
Check the voltage at CN118-1 on the main board.
24V 0V
Replace the main board.
Replace the toner supply clutch solenoid.
1 December 1990
6-16