Lexmark 4039-1XX Manuale Utente

Diagnostic Information

sure the duplex table cover (floor) is correctly snapped in place at its 
front and rear and that the gear block assembly is correctly snapped 
into the bottom cover. Run duplex diagnostics tests #1 and #2 to 
make sure there is no slippage in the paper path. Make sure the 
flags of the duplex unit input and exit sensors move freely.

While the 23 is displayed, press and hold the Return button while 
pressing the second button from the top, and note the 7th and 8th 
digits from the left. If they are 01 or 03, there is a problem with the 
duplex input sensor signal. Remove the duplex top cover and table 
cover. Measure the voltage on JP6-3 of the duplex system board; it 
should fluctuate from 0 to +5VDC as you toggle the sensor flag. 
Check the sensor cable continuity. If the sensor and the cable are 
good, replace the duplex system card.

If the 7th and 8th digits are 04, there is an exit sensor problem. 
Remove the duplex top cover and table cover. Remove the paper 
tray so you can reach the sensor. Measure the voltage on JP6-8 of 
the duplex board; it should fluctuate from 0 to +5VDC as you toggle 
the sensor. Check the sensor cable continuity. If the sensor and the 
cable are good, replace the duplex system card.

The fan should run continuously when the printer is powered up, 
unless the printer is in Power Saver mode. Check that the fan rotates 
freely when spun manually and that the cable connections to the fan 
are OK. The voltage at (10P/10R/12R/12C/12L) J5-6 (16L) J3-6 
should be approximately +24VDC when the top cover is up. Short 
pin 6 to ground to test the fan; if the fan does not run check the 
continuity of the fan cable before replacing the fan. A bad fan can 
pull down the +24V line even if it runs; check that (10P/10R/12R/
12C/12L) J5-7 (16L) J3-7 has between +21 and +26VDC when the 
fan is running; if it does not, replace the system board.