Xerox Phaser 7750DXF, Service Manual

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Error Messages and Codes 3-33
Fan Failure, Code 48
The machine logic detected a failure of the Fuser fan, LVPS fan, or rear fan.
Troubleshooting References
Applicable Parts Wiring and Plug/Jack Map References
■
Fuser Fan
■
LVPS Fan
■
Rear Fan
Troubleshooting Procedure
Step Actions and Questions Yes No
1 1. Enter service diagnostics and run the
fan test.
2. Does the fuser fan rotate at a high
speed?
Go to step 4. Go to step 2.
2 1. Check for voltage at J222-4.
2. Does the voltage m24 VDC?
Go to step 3. Check the wiring
to the fuser fan, if
the wiring is OK,
replace the
engine control
board.
3 Does the front panel indicate the fans are
ON? Replace the fan. Check the wiring
to the fuser fan, if
the wiring is OK,
replace the
engine control
board.
4 Does the rear fan revolve at high speed? Go to step 7. Go to step 5.
5 1. Check for voltage at J552-1.
2. Does the voltage m24 VDC?
Go to step 6. Check the wiring
to the rear fan, if
the wiring is OK
replace the
interface board. If
the problem
continues,
replace the
engine control
board.