Brother HL-2290 Service Manual page 74

 Error code F900
The spec code was not entered correctly.
Step
The power was turned OFF while
1 function code 74 was running.
2 Main PCB failure
Memo:
Press the [▲] or the [▼] under error code F900 display to select the maintenance mode.
Cause
2-52
Remedy
Reenter the spec code. (Refer to
Setting by spec (Function code 74)" in
Chapter 5.)
Replace the main PCB ASSY.
"1.3.16
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