Power Service Check - Lexmark Medley 4012-009 Service Manual

4012-0XX

Power Service Check

The operator panel power key does not control line power. With the
machine turned off the power supply is still active and there is volt-
age to both the fax and printer boards. To remove power you must
unplug the machine.
FRU
1 Power Supply
2 Printhead Cable
Parallel Cable
3 Printer Board
4 Fax Board
11
Action
Disconnect J2 from the fax board, J11
from the printer board and check the fol-
lowing voltages on both power supply
cables:
Pin-1 to GND = +5 V dc
Pin-3 to GND = +34 V dc
If you do not have correct voltage, replace
the power supply. Be sure to unplug the
machine before you reconnect the power
supply to the boards.
Unplug the machine. Disconnect one of
the listed components and plug in the
machine. Look for a symptom change.
Check the failing part for shorts and
replace as necessary. Repeat this proce-
dure for the remaining listed parts.
Disconnect the fax board from the printer
board. Run the Print Engine Test. If the
test does not run and there are no
mechanical problems, replace the printer
board.
Check for +5 V dc at the fax board J9-4,
and check for +34 V dc at J9-2. If the volt-
ages are incorrect replace the fax board.