Lexmark C750 Service Manual page 160

5060-00x
No indication that the chad box is full, no message
Use the "HCOF error code table" on page 2-122
Step Action and questions
1 Make sure the chad box is correctly installed in the
finisher.
Is the chad box correctly installed.
2 Make sure the chad box cable S5 is properly
connected to CN5 on the finisher system board.
Is the cable properly connected?
3 Make sure the chad box cable is properly connected to
the chad box sensor located above the box.
Is the cable properly connected to the sensor?
4 Check the chad box sensor with a voltmeter. Empty the
chad box. Check the voltages on CN5. The voltages
read the following approximate values with the chad
box empty:
Connector pin Voltage
CN5-1
CN5-2
CN5-3
Are the voltages correct?
5 Check the sensor by placing the chad box or a piece of
paper in front of the sensor. As the chad box or piece of
paper is moved away from the front of the sensor the
voltage on CN5-2 should change from +5 V dc to 0 V
dc.
Does the voltage change?
Chad box full message when chad box is not full
Step Action and questions
1 Make sure the chad box is correctly installed in the
finisher.
Is the chad box correctly installed?
2 Check the chad box sensor with a voltmeter. Empty any
material that is in the chad box. Measure the voltage on
CN5-2. The voltage changes from approximately +5 V
dc to 0 V dc as the sensor is activated.
Does the voltage change?
2-126
Service Manual
to help diagnose the problem.
+5 V dc +5 V dc supply
+5 V dc sensor signal
0 V dc Ground
Yes No
Go to step 2 Install the chad box
correctly.
Go to step 3 Install the cable
correctly.
Go to step 4 Install the cable
correctly.
Go to step 5 Replace the
finisher system
board.
Problem solved Replace the chad
box sensor.
Yes No
Go to step 2 Install the chad box
correctly.
The sensor is Replace the
working correctly. finisher system
board.