Brother HL-L8250CDN Service Manual page 291

1.3.4 Operational check of LCD (Function code 12)
<Function>
This function is used to check that the LCD on the control panel is operating normally.
<Operating procedure>
Model without touch panel
(1) Press the
the maintenance mode. Then, press the OK key.
(2) Each time you press the Go key, the LCD cycles through the displays as shown below.
(3) When the Cancel key is pressed, the machine returns to the initial state of the
maintenance mode, regardless of the display status.
<Display 1>
Backlight
LCD
Data LED
Error LED
<Display 2>
Backlight
LCD
Data LED
Error LED
<Display 3>
Backlight
LCD
Data LED
Error LED
<Display 4>
Backlight
LCD
Data LED
Error LED
or key to display "MAINTENANCE 12" on the LCD in the initial state of
: OFF
: Display of all dots
: Green ON
: Orange ON
: OFF
: Display of 16 dots in
2 lines
: Green ON
: Orange ON
: OFF
: Display of no dots
: Green ON
: Orange ON
: ON
: Display of no dots
: Green ON
: Orange ON
Display 1
Display 2
Display 3
Display 4
5-8
Fig. 5-3
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