Xerox Phaser 7400 Service Manual

Print-Quality Troubleshooting 5-19
Random Bands, Lines, Marks, or Missing Spots
There are areas of the image extremely light or are missing entirely and do not appear
to be a repeating defect or in a single color.
Caution
Leaving an Imaging Unit exposed to light for periods in excess of a 10 minutes
can quickly degrade its performance and result in early failure.
Initial Actions
■ Using a flashlight, carefully examine the area around the Imaging Units and
the openings between the Imaging Units and LED Heads. Small
obstructions, such as hair or fibers, can create streaks
■ When troubleshooting, print a test print on at least letter size paper for
diagnosing this problem. The problem may be a repeating defect that is not
noticeable on smaller media.
■ Random missing spots can also be associated with “Cold Offset”, which lifts
toner off the page in certain areas. Usually this will occur in high-coverage
areas where the fuser temperature is not high enough to fuse the toner on the
media. This causes toner to be redeposited further down the page.
Troubleshooting Reference Table
Applicable Parts Example Print
■ Imaging Unit
■ Fuser
■ Transfer Unit
■ Engine Control Board
s7400-327

Xerox Phaser 7400 Specifications

General

Color	Yes
Print technology	Laser
Maximum resolution	600 x 1200 DPI
Time to first page (black, normal)	12 s
Print speed (black, normal quality, A4/US Letter)	40 ppm
Print speed (color, normal quality, A4/US Letter)	36 ppm
Storage media	HDD
Internal memory	512 MB
Processor model	PowerPC
Maximum internal memory	1 MB
Internal storage capacity	20 GB
Total input capacity	800 sheets
Maximum input capacity	3000 sheets
Paper tray 2 input capacity	350 sheets
Auto document feeder (ADF) input capacity	1650 sheets
Maximum print size	297 x 420 mm
Paper tray media types	Envelopes, Labels, Transparencies
Non-ISO print media sizes	Executive (184 x 267mm), Folio (media size), Letter (media size), Statement (140 x 216mm), Legal (media size)
Maximum ISO A-series paper size	A3
Power requirements	100-240V, 50/60Hz
Networking features	Fast Ethernet
Supported media weight(s)	270 g/m²
Maximum operating temperature range (T-T)	10 - 32 °C
Certification	FCC p.15 A, CE
Storage temperature (T-T)	-20 - 60 °C
Operating temperature (T-T)	-4 - 140 °F
Storage relative humidity (H-H)	10 - 95 %
Operating relative humidity (H-H)	20 - 80 %
Maximum duty cycle	150000 pages per month

Weight and Dimensions

Dimensions (WxDxH)	1438 x 623 x 975 mm