Lexmark C78x Service Manual page 101

927.03 error code service check
RIP fan
Step Actions and questions
1 Turn the power off, manually spin the fan, and check
that it rotates freely.
Does the fan rotate freely?
2 Check the RIP fan cable connection to the system
board JR1 for correct installation.
Is the cable installed correctly?
3 Disconnect the RIP fan from JR1 on the system board,
and check the voltages on JR1.
Pin
JR1-1
JR1-2
JR1-3
JR1-4
Are the voltages correct?
930.09 error code service check
LVPS
This problem with the fuser circuits is usually the zero crossover signal from the LVPS not working correctly.
Step Actions and questions
1 LVPS cable—check the LVPS cable to J17 on the
system board to make sure it is seated correctly. Go to
"System board" on page
Is the cable seated correctly?
2 Voltage checks—Disconnect JCVR1 from the system
board assembly. Go to
Check the voltage at J17, on the cable. It measures
approximately +3.7 V dc.
Is the voltage correct?
Fan on Fan off Fan
disconnected
Fan switch on
+1.6 V dc +3.3 V dc +3.3 V dc
0 V 0 V 0 V
+1.9 V dc 0 V dc 0 V
+24 V dc +24 V dc +24 V dc
5-8.
"System board" on page
Yes
Go to step 2
Go to step 3
Replace the RIP
fan. See "RIP
fan removal" on
Fan
page 4-87.
disconnected
Fan switch off
+3.3 V dc
0 V
+2 V dc
+24 V dc
Yes
Go to step 2
Go to step 3
5-8.
5061
No
Replace the RIP
fan. See "RIP
fan removal" on
page 4-87.
Install the cable
correctly.
Replace the
system board.
See "System
board removal"
on page 4-90.
No
Install the cable
correctly.
Replace the
following FRUs in
order:
1. LVPS
assembly.
See "LVPS
assembly
removal" on
page 4-53.
2. System
board. See
"System
board
removal" on
page 4-90.
2-57
Diagnostic information