Lexmark 4039-1XX - Manual (Page 40)

26 Service Manual
4039-1XX
If paper feeds but stops undamaged in the paper path there may be
a sensor problem. Run the diagnostic test for the input and exit
sensors replace as necessary. Check the continuity of the cable
before replacing the sensor. The input sensor signal is on (10P)
J20-6 (10R/12R/12C/12L) J20-11 (16L) J17-11; the output sensor
signal is on (10P/10R/12R/12C/12L) J19-8 (16L) J16-8. The voltage
should be 0VDC when there is no paper in the sensor and +5VDC
when paper is present.
If paper is jamming, clean the paper path of obstructions or repair
any damaged parts. Very thin or thick paper, labels, transparencies,
or card stock will have a higher jam rate than regular xerographic
paper. Check the condition of the paper in the tray and verify that the
tray is installed correctly.
If paper is curling badly enough to cause a problem feeding or
stacking, see
“Fuser Temperature And Warm-Up Time” on page 39 .
Paper Feed, Duplex Unit
Check that all gears and belts are working correctly both in the
duplex unit and on the tray top cover, and that the gear on the tray
top cover engages the gear on the duplexer.
If paper is jamming in the table cover area, make sure the table
cover is properly installed. Run diagnostics Duplex Test 1 to make
sure the paper is feeding far enough into the duplex unit before
reversing. Examine the condition of all rollers.
If paper is stopping or jamming as it is fed back across the top of the
paper tray, run diagnostics Duplex Test 2 to make sure there is no
slippage in the paper path. Make sure the paper tray top cover is not
damaged. Cold paper curl can also cause jams here;
see “Fuser
Temperature And Warm-Up Time” on page 39 .
If paper is jamming at the front exit, verify that the front exit deflector
switch is functioning by disconnecting (10P/10R/12R/12C/12L) J19
(16L) J16 and checking the resistance from pin 1 to pin 2 as you
operate the switch.
Also see “23 Paper Jams” on page 18