Image formation Issue, Could be any Color , Drum , Developer or more.
When you check the printing status to find out that the color printing ratio is less than 5%, color toner
low density might be the cause.
Turn the code 08-2692 “Prevention of color toner low density / ON/OFF setting” to ON, and then set
number of sheets to be judged at the code 08-2693 “Prevention of color toner low density / Judged
number of sheets setting”.
If the color printing ratio is 5% or more, check the following.
1.Check if there is any abnormality on the hand grips and rods of the main charger cleaner. Correct if
2.Check if the drum is rotated properly by turning the coupling of the developer unit. Correct the auger
and the surrounding hardware if not.
3.Check if the connectors CN337, CN346 and CN358 of the LGC board are disconnected from the
laser optical unit or the harnesses are open circuited.
4.Check if there is any stain or scratch on the glass surface of the laser optical unit. Clean or correct if
5.Check if there is any stain on the image quality sensor and Image position aligning sensors.
6.Check if the sensor shutter is working properly.
* If the error still occurs, check the following.
< Invalidating color registration control >
(1)Turn the power ON while  and  are pressed simultaneously.
(2)Key in “4546”, then press the [START] button. (08-4546: Position adjustment control / Mode setting)
(3)Set the value to “0” (not performed automatically).
(4)Turn the power OFF.