Lexmark 25**-100, Service Manual

Page: 51 / 188

Diagnostic information
2-31
25XX-100, -110
Print speed service check
The speed of the 25XX printers varies with the font, forms thickness
setting, and printhead temperature. Graphics output may print slowly
due to data throughput limitations. Thermal sensing is built into the
printhead on 25XX printers and protects the printhead from
overheating.
6 Logic board If no problem is found with the other
components, but the power problem still
remains, replace the logic board and reset the
bidirectional print adjustment. Go to
“Bidirectional print adjustment” on
page 4-4
.
FRU Action
1 Head Gap sensor Check the function of the Head Gap sensor by
turning the printer on while pressing the
Macro
button. Open the operator panel to the second
level and do the following:
• With the Forms Thickness lever at 1, Macro
LED 1 lights.
• With the Forms Thickness lever at 2 and 3,
Macro LED 2 lights.
• With the Forms Thickness lever at 4 through
7, Macro LED 3 lights.
Disconnect the Head Gap sensor from
connector CN4 on the logic board. Place the
Forms Thickness lever in position 1 and verify
continuity at the following pin locations:
CN4 - 1 and CN4 - 2
CN4 - 2 and CN4 - 3
Place the Forms Thickness lever in positions 2
and 3 and verify continuity at the following pin
location:
CN4 - 1 and CN4 - 2
Verify that there is no continuity at Forms
Thickness lever positions 4 through 7.
FRU Action