Lexmark 4500-00 Series, Service Manual

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Service Manual
4500
Hot fuser service check
Make sure the correct voltage lamp is installed. The voltage rating is stamped
on one of the lamp contacts.
Low voltage power supply (LVPS) service check
FRU Action
Fuser Disconnect the thermistor cable from
J7 (engine board in E320/E322) or
J14 and J22 (if used) (controller card
in E220/E321/E323).
Measure the resistance across the
thermistor cable. See
“Connector
locations ” on page 5-1 for more
information. Replace the fuser
assembly if the resistance is lower
than 1k ohm or shorted.
Note: Resistance measures
approximately 240K ohms
when cool and 1.4K ohms
hot.
FRU Action
Low voltage power supply board
(LVPS) Set meter for AC line voltage.
Check for AC line voltage on CN1
between pins 1, and 3.
• If line voltage is present,
disconnect the CN3 cable plug
from the LVPS board.
• If the voltage is not present,
replace the power switch or check/
correct missing line voltage.
Use the LVPS connector table
(
page 5-1 ) and check for correct
voltages.
If voltage is not present or correct,
replace the LVPS fuses and/or the
LVPS board.