Toshiba FC-22 manual Troubleshooting of Image, Color deviation Symptoms

4.2 Troubleshooting of Image

(1)Color deviation <Symptoms>

Condition	Location	Phenomena	▲
All modes	White void areas, color blur	Color
		deviation
Text mode	Black text outlines in color	White void		▲
Text/Photo mode	background
Photo mode	Color blur in outline of line	Color
Map mode	or text	deviation
			▲

A B C A B C

A B C A B C

A B C A B C

Defect area	Step		Cause		Check Item
		Main-Classification	Sub-Classification	Specific-Classification
	1				Output build-in grid pattern on A3/LD.
Color registration	2	Control error or			Check grid pattern.
Control		poor optimization
Abnormal paper	3	Paper transport	Low speed	Adjustment defect	Check grid pattern.
transport speed		speed in
		registration section	Low speed	Registration roller
				aging change
			Low speed	Registration roller	Check condition of registration rubber roller
				life worn out	surface.
			High speed	Adjustment defect	Check grid pattern
	4	Paper transport	High speed	Adjustment defect	Check grid pattern.
		speed in fuser unit
					Feed the paper with the front door open and
					check the paper transport between transfer
					belt and fuser unit.
					No defect in normal paper mode, but in thick
					paper 3 mode, deviation occurs in order (Y)
					MCK, at trailing edge of A3/LD sheet.
Drum drive system	5	Drum rotation	Unstable	Motor abnormal	Run operation check in test mode.
				Control circuit	Run operation check in test mode.
				abnormal
		Drum motor	Inadequate	Adjustment defect	Re-check values set for drum motor rotation
		rotation speed			speed.
		Drum coupling	Loose coupling		Check grid pattern.
			Damage
			Deformation
Transfer belt system	6	Transfer belt	Deformation or		Check grid pattern.
			damage		Check condition of transfer belt edge
		Drive roller	Slipping	Stain	Check grid pattern.
					Check condition of roller surface.
		Large driving load	Used toner	Over capacity	Check grid pattern.
			Cleaning blade	Peeling
Laser optical unit	7	Tilt adjustment	Adjustment mech-		Check grid pattern.
		mechanism	anism defect
		Reflection mirror			Check grid pattern.
		warp
		fθ lens characteris-			Check grid pattern.
		tic defect

FC-22 TROUBLESHOOTING 4 - 54 January 2000 © TOSHIBA TEC