Brother DCP-L8400CDN Service Manual page 451

1.3.35 Developing bias voltage correction (Function code 83)
<Function>
This function performs developing bias voltage correction to fix the density of each color toner
when printed color is not correct.
Note:
Before this function is performed, there is a need that the
density sensor (Function code 72)" in this chapter
performing this maintenance mode 83 after replacing the main PCB ASSY, make sure to
perform the
<Operating procedure>
(1) Press the 8 and 3 keys in this order in the initial state of the maintenance mode.
The machine displays "PLS WAIT 83" on the LCD and starts the developing bias voltage
correction.
(2) When developing bias voltage correction is completed, "MODE KYMC ****" is displayed
on the LCD. When you press the Mono Start key, the machine returns to the initial state
of the maintenance mode.
(* represents any number from 0 to 3.)
Note:
If developing bias voltage correction fails, "ERROR 83" is displayed on the LCD. Display the
error message by pressing the
the error message.
Error message
FAILED DEVBIAS
TONER EMPTY #
Cover is Open
Replace Toner
* # indicates the toner color (Y, M, or C) of which cartridge became empty.
"1.3.28 Sensitivity adjustment of density sensor (Function code 72)"
key, and take the following measure that corresponds to
Remove the error factors with the following operations and press the
Mono Start key to clear the error.
- Re-insert the toner cartridge in the correct position.
- Replace the toner cartridge.
- Replace the drum unit.
- Replace the waste toner box.
- Replace the belt unit.
- Replace the registration mark sensor unit.
*
Replace the empty toner cartridge and press the Mono Start key to
clear the error. After the sensitivity adjustment of the density sensor
(Function code
is compensated again.
Close the front cover.
Replace the black toner cartridge and press the Mono Start key to
clear the error. After the sensitivity adjustment of the density sensor
(Function code
is compensated again.
"1.3.28 Sensitivity adjustment of
has been done more than once. When
Measure
72) is performed, the developing bias voltage value
72) is performed, the developing bias voltage value
5-67
first.
Confidential