Power supply fan service check, 912—power supply fan service check, 912—power supply fan service check” on – Lexmark 5021-0XX User Manual
Page 129

Diagnostic information
2-51
5021-0XX
912—Power supply fan service check
Step
Questions / actions
Yes
No
1
Turn printer off and remove
I/O board shield. See
for steps to
remove I/O board shield. Is
cable properly connected
to I/O board connector
DCN20?
Go to step 2.
Properly connect
cable.
2
Ensure rear cover
assembly cover is shut.
Override top and front
cover interlock switches.
For location, see
“Interlock switch
locations” on page 5-8
Reconnect operator panel.
Turn printer on and check
for 24VDC between DCN20
pin 1 and power ground
(you can touch negative
lead of voltmeter to metal
bracket that holds I/O
board to obtain ground.) Is
voltage present and
correct?
Replace power
supply fan
assembly. See
“Power supply
fan removal” on
page 4-74
.
Retest printer. If
error clears,
problem solved,
otherwise go to
step 3.
Replace I/O
board. See
.
Retest printer. If
error clears,
problem solved,
else go to step 3.
3
Turn printer off and check
cable that connects engine
controller board connector
I1CN to I/O board
connector DCN1 for
continuity and pin shorts. Is
cable okay?
Replace engine
controller board.
See
controller
board removal”
on page 4-55
Replace cable.