Lexmark 4039-1XX Manuale Utente

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18
Service Manual
4039-1XX
If some voltages are present, but all are not correct, disconnect all 
cables except the LVPS from the system board. POR and verify that 
the LVPS voltages are correct. Turn the power back off and, one at a 
time, reconnect the system board cables, powering on in between 
each connection and checking the voltages. The connection which 
causes the voltages to be wrong indicates which component is bad. 
Repair or replace the failing component or cable as necessary. 
Duplex 
The duplexer should home — the front shafts should turn and the 
input deflector should move — immediately when you install the 
duplexer with the printer already powered on, or when you POR the 
printer with the duplexer installed. This means the duplexer has 
completed its internal tests and is ready to communicate with the 
printer.
If the duplexer does not home it is either damaged or is not receiving 
+34VDC from the printer.
To check the connection from the printer system board to the duplex 
system board, remove the duplex top cover and table cover. 
Disconnect the duplex cable from the printer system board. From left 
to right (10P: top to bottom), the voltages on the printer system 
board connector pins should be 0, +34VDC, 0, +5VDC, 0, and 
+5VDC. With the cable connected, these voltages should also be at 
duplex system board JP4-1 through JP4-6. If you do not find a cable 
or voltage problem, replace the duplex system board.
A 933 error indicates that communication between the printer and 
duplexer had been established but has been lost. Check the cable 
as above; if the error persists replace the duplex system board.
23 Paper Jams: Examine the paper path in the duplex unit and in 
the fuser exit area for paper or other obstructions. Make sure the 
duplex unit is positioned correctly on the printer, and that the gear at 
the bottom of the duplex unit meshes with the gear on the top of the 
paper tray. Check that the paper is fed with no skew or binds from 
the duplexer into the metal channel at the right edge of the tray 
cover. The tray roller should move the paper forward when the tray 
gear is turned, but allow the paper to be pulled by the D-roll when it 
picks. Make sure the belt to the duplex DC motor is in place. Make