Lexmark 4227 - Forms Printer B/W Dot-matrix Service Manual page 47

4227-300
FRU/Symptom
5 PE Sensor
TOF Sensor
PSet Sensor
Jam Sensor
6 Paper Select
Sensor
Action
The printer has four sensors in the paper path,
plus one which detects the position of the
Paper Select lever. Enter the Service Menu
and perform the sensor tests.
• PE Sensor—Rounded flag, detects the
presence of paper at the platen.
• TOF Sensor—Sharp flag, determines TOF
at paper load.
• PSet Sensor—Paper set, detects presence
of paper in the tractors and looks for end of
forms.
• Jam Sensor—Senses the holes in the paper
and detects paper jams by the lack of paper
movement.
When the PSet sensor detects EOF, it lets
printing continue to the bottom of the form.
When the PE sensor detects no paper, it stops
print within a few lines.
The jam sensor stops printing after about
50 mm of no signal change; for example, if 50
mm of pinfeed is removed from a sheet, the
sensor stops printing. Less than 50 mm will
probably be ignored. Therefore, the paper
motion must have stopped for the equivalent of
about 12 printed lines to cause a jam.
If either the PE or the PSet sensor detects no
paper during print, printing stops at the end of
the current page.
The Tractor 2 option also has PSet and Jam
sensors on the left tractor.
Enter the service menu and perform the sensor
tests.
Replace any failed or damaged sensors.
Enter the Service Menu and perform the
Sensor Test 2 for "Lever."
Move the Paper Select lever to test the sensor.
Replace any sensor if failed or damaged.
Diagnostic information
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