https://www.manualslib.com/manual/794794/Brother-Dcp-7055.html?page=106
Brother DCP 7055 Service Manual Error Code Ee ef
Quoting from the free manual Page 2-69:
? Error code EF
Print Unable EF
Turn the power off and then back on again.
The supplied power is unstable.
Step
The irregular power supply is
detected
1
2
Main PCB failure
Note:
• The irregular power supply detection error (Machine Error EF) occurs when there is a
large fluctuation in the power supply voltage supplied to the machine.
In this case, if the same power supply is used, the same error might occur again even if
the low voltage power supply PCB ASSY is replaced.
×