Brother MFC620CN Service Manual page 369

Loading the update programs/data onto the flash ROM of the machine
After replacing the main PCB with a new one
After the installation procedure of the printer driver, proceed to the firmware loading operation.
When the power is first applied to the FAX machine equipped with a new main PCB, the machine
automatically enters the maintenance mode.
Make sure that the machine is connected with your PC using a USB cable.
NOTE: Never turn off the machine or PC or unplug 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.pjl) 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: New main PCB doesn't accept the file having the extension .upd.
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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