HP LaserJet 4101mfp Problem, Solution, Condition, Table 23. Image defects (continued)

Table 23. Image defects (continued)

Problem	Condition	Solution
Page skew	The ADF unit or scan unit needs to	● Calibrate the scan unit. See
	be calibrated.	“Calibration” on page 47 and/or
		“Performing manual calibration” on
		page 48.
	ADF input tray guides are not	● Verify that the ADF guides are not
	properly adjusted.	adjusted to tightly against the media or
		to loosely and separate from the
		media.
	ADF paper delivery guide (clear	● Clean the ADF paper delivery guide.
	mylar strip) is dirty.	See “Cleaning the ADF delivery guide
		(clear mylar strip)” on page 37.
Vertical lines	Dirty glass, whiteboard cover, ADF	● Clean the glass, whiteboard cover,
	delivery guide (clear mylar strip).	and/or ADF delivery guide (clear mylar
		strip). See “Cleaning the product” on
		page 36.
	ADF unit and/or scan unit is	● Calibrate the scan unit. See
	improperly calibrated.	“Calibration” on page 47 and/or
		“Performing manual calibration” on
		page 48.
	Deformed pickup roller.	● Replace the deformed roller. See “ADF
		pickup roller” on page 74.
	Foreign substances are deposited	● Clean the pickup roller (flatbed).
	on the pickup roller.	● If the problem persists, replace the
		pickup roller. See “ADF pickup roller”
		on page 74.
	Defective optical-unit CCD driver.	● Replace the optical unit. See “Optical
		unit” on page 95.
	Scars on the mirrors or lens in the	● Replace the flatbed optical unit. See
	flatbed optical unit.	“Optical unit” on page 95.
Image shifted	Image is shifted vertically,	● Calibrate the scan unit. See
	horizontally, or both ways on the	“Calibration” on page 47.
	page. Scan unit is improperly
	calibrated.

Image skips	Image shifts on the page or starts	●	Verify that the ADF document-detect-
	and stops at irregular intervals		sensor (PS2) and leading-edge-sensor
			(PS1) flags move freely. See
			“Document-detect sensor (PS2)” on
			page 68, “Leading-edge sensor (PS1)”
			on page 68, and “ADF components”
			on page 56.
Unexpected image	Unexpected images when using the	●	Verify that there is not any media left
	ADF to make copies.		on the glass from a previous copy job.

C9148-90909 7 Troubleshooting 139