• Electrical noise on the power supply line

557	Zero cross waveform signal error
	The waveform of the zero cross signal was detected out of range.	• Electrical noise on the power supply line
559	Consecutive fusing unit paper jams
	Three consecutive paper jams occurred in the fusing unit. The paper jam counter for the fusing unit reaches 3 times. The paper jam counter clears after the paper feeds correctly. Note: This SC is issued only if SP1159 is set to "1".	• Remove the paper jam in the fusing unit. • Make sure that the paper path in the fusing unit is clear.
590	Exhaust fan motor error
	The CPU detects an exhaust fan lock signal for more than 3.5 seconds.	• Poor connection of the exhaust fan motor • Too much load on the motor drive