Brother HL-5440D Service Manual page 58

LED
The registration front sensor does not detect paper
pass within the specified time after the first side was
printed in duplex printing mode.
The eject sensor remains ON (paper pass detected)
for more than the specified time even after the
registration rear sensor detected the end of paper
pass.
Detected discharge that may be attributable to dirty
corona wire on the drum unit.
Detected that DIMM was faulty or was mounted
incorrectly.
An error occurred during access to the DRAM in the
main PCB.
An error occurred in the ROM check sum.
Program error
Type of problem
2-22
Error Refer
codes to:
5700 2-34
8400 2-41
7D00 2-40
C900 2-50
3B00 2-31
E000 2-52
E100 2-52
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