Brother MFC620CN Service Manual page 371

After replacing the main PCB with the one used for other machines or when updating
program/data
After the installation procedure of the printer driver, proceed to the firmware loading operation.
If the printer driver has been installed so that you start from loading firmware, unplug the power
cord from the electrical outlet.
Make sure that the machine is connected with your PC using a USB cable.
MFC620CN/425CN/420CN/410CN/215C/210C and FAX2440C
While holding down the 5 key, plug the power cord into an electrical outlet.
DCP315CN/310CN/120C/117C/115C/110C
While holding down the Number of Copies key, plug the power cord into an electrical outlet.
The machine should show the black and white pattern on the LCD.
NOTE: Never unplug the machine's or PC's power cord or the USB cable during loading.
(1) Run "FILEDG32.exe."
The Filedrgs window will appear as shown below.
(2) Drag and drop the firmware (e.g., LZ0023_A.upd) onto the BHL2-Maintenance Printer icon in
the Filedrgs window shown above.
NOTE: Use a firmware file after extracting. It is a self-extracting file having the
extension .exe. Double-click the exe file to extract it.
NOTE: If the main PCB isn't new or blank, use the file having the extension. upd. It prevents
from writing the wrong program which the PCB doesn't accept.
When loading operation starts, the machine beeps intermittently. After approx. 2 to 5 minutes,
the loading operation is complete and the machine automatically reboots and returns to the
standby state.
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