Konica-Minolta bizhub C550

Detection timing

Type	Description
Detection of misfeed at manual bypass feed section	• The leading edge of the paper does not turn ON the tray1 vertical transport sensor (PS4) even after the lapse of a given period of time after the manual bypass starts to feed paper.
	• The bypass paper limit sensor (PS35) is not blocked after the lapse of a predetermined period of time after the paper lifting plate is started to be raised from the standby position to the paper feed position.
	• For paper fed from the manual bypass tray, the bypass paper lower sensor (PS36) is not blocked after the lapse of a predetermined period of time after the paper lifting plate is started to be lowered from the paper feed position to the standby position.
Manual bypass feed section loop registration reversing jam	• For paper fed from the manual bypass, loop forming has not been complete before a sheet enters the timing roller because the rise timing of load to perform registration is earlier than the rise timing of load to form a loop.
Manual bypass feed section TOD permit waiting jam	• For paper fed from the manual bypass, TOD permit continues to be disabled for a predetermined period of time after the timing of TOD output.

Relevant electrical parts

Bypass paper feed motor (M27)
Tray 1 vertical transport sensor (PS4)
Bypass paper limit sensor (PS35)
Bypass paper lower sensor (PS36)

Paper feed/transport drive board (PFTDB)
Printer control board (PRCB)

Action

Step	Action	Control signal	Location
1	Initial check items.
2	PS4 I/O check, sensor check	PFTDB CN4PFTDB-8 (ON)	P-5
3	PS35 I/O check, sensor check	PFTDB CN26PFTDB<B>-10 (ON)	P-12
4	PS36 I/O check, sensor check	PFTDB CN26PFTDB<A>-11 (ON)	P-11
5	M27 operation check	PFTDB CN26PFTDB<B>-1 to 4	P-12
6	Change PFTDB
7	Change PRCB