e-STUDIO3511/4511 TROUBLESHOOTING 5 - 78 November 2003 © TOSHIBA TEC
5.1.19 Toner density control related service call
[CF20] Toner density detection voltage abnormality
(1) Specify the developer unit with the abnormality by checking the setting values of 08-824-0 to 08-
824-2. (When the value is “1”, an abnormality occurs.)
(2) Correct the defective section of the unit specified in (1) with the following procedure.
Is the developer material transported properly? Is the form of magnetic brush is normal?
NO 1. Check if the amount of the developer material is normal or any foreign matter is
mixed in.
2. Correct the transport mechanism of developer material.
3. Check the polar position and correct if necessary.
YES
Is the color auto-toner sensor stained?
YES Clean it.
NO
Is the color auto-toner sensor shutter solenoid working normally? (Perform the output check: 03-125/
175)
Is the color auto-toner sensor working?
NO 1. Check if the connectors or joint connectors of the color auto-toner sensor shutter
solenoid and color auto-toner sensor are disconnected.
2. Check if the connector CN356 on the LGC board is disconnected.
3. Check if the connector pins are disconnected or the harnesses are open circuited.
4. Replace the color auto-toner sensor shutter solenoid.
5. Check if the conductor pattern on the LGC board is short circuited or open
circuited.
6. Replace the LGC board.
7. Replace the color auto-toner sensor and perform “Enforced correction of color
auto-toner sensor light amount (05-208)”.
YES
Is the color auto-toner sensor shutter opening position correct? (Perform the output check: 03-125/175)
NO Adjust the install position of solenoid so that the sensor holder will touch and face
the positioning component when opening the shutter.
YES
1. Check if the conductor pattern on the LGC board is short circuited or open circuited.
2. Replace the LGC board.
(3) When the correction is completed, reset the values of 08-824-0 to 08-824-2 from “1” to “0” to clear
the abnormality.