Printronix T3204 Maintenance Manual page 55

Step Check Item
9. Examine the drive roller while pressing the FEED button. Does
the roller turn in the correct direction?
10. Examine the drive roller. Does it turn enough to feed the media
outward?
Troubleshooting Procedure 3. – Media Sensor Faults
Step Check Item
1. Check the media sensor for obstructions. Labels, dirt and
powder residue from label stock can sometimes block the
sensor lens. Is the media sensor clean?
2. Unplug the printer and remove the cover. Locate the Operator
Panel PCBA connector. Inspect associated cables for proper
connection and damage. Are both cables O.K.?
3. Unplug the media sensor cable from J7 on the Printer
Controller PCBA. Turn the printer ON and check the voltages
between chassis ground and pins 1, 3 and 5 on J7 of the
Printer Controller PCBA. This voltage should be +5 VDC. The
voltage on pins 4 and 6 should be less than one volt, and
should be zero volts on pin 2. Are all voltages correct?
4. Turn printer OFF and re-connect all unplugged connectors.
Turn printer ON and place label stock, with two labels removed
to expose the label backing, between the sensor brackets. The
voltage between ground and TP1 on the Printer Controller
PCBA should be greater than 2.1 VDC with the label under the
sensor and less than 0.5 VDC with the backing under the
sensor. Are both of these measurements correct?
Troubleshooting
Result Corrective Action
YES Go to Step 10.
NO Replace the Printer Controller
PCBA.
YES This problem can be caused
by a worn roller or misaligned
parts within the printhead
assembly.
NO 1) Replace the Power Supply
PCBA.
2) Replace the Printer
Controller PCBA.
Result Corrective Action
YES Go to Step 2.
NO Remove any objects blocking
the sensor. It may be
necessary to remove the
media sensor from the
printer.
YES Go to Step 3.
NO Connect cables properly or
replace if damaged.
YES Go to Step 4.
NO Replace Printer Controller
PCBA.
YES Media sensors are OK. Go to
Procedure 4.
NO 1) Replace the sensor
assembly.
2) Replace the Operator
Panel PCBA.
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