Brother HL-5440D Service Manual page 219

(7) Enter the number (last digit) on the laser serial number label attached to the location
shown in the illustration below in the [K= ] field.
Laser plate
(8) Enter the numbers (from sixth last digit to second last digit) on the laser serial number
label in the [Scanner Video Clk] field.
(9) Click the [OK] button. The serial number and the adjusted value of the laser unit are
written to the machine.
(10) Turn OFF the power switch of the machine.
Laser serial number label
Fig. 4-2
4-9
Laser unit
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