Epson Stylus Color 980 Service Manual page 99

EPSON Stylus Color 980
Table 3-31. Cleaning does not Solve the Print Problem (continued)
Step Check Point
6 Is any ink tube Referring to the figure below, check the following
disconnected from points:
the cap unit?
• Connection between two tubes and the bottom of
the cap (Remove the whole cap from the unit to
check the connection.)
• Connection of each tube and the separator.
• Connection of one tube at the bottom of the valve
7 Is the FFC Remove the printhead unit from the carriage unit, and
disconnected from bring the printhead surface side upward to check that
the printhead two FFC is properly connected. Even though no slant
board? connection nor disconnection is found, disconnect
the FFC once and install them again.
Troubleshooting
Action
Overview
Table 3-32. Cleaning does not Solve the Print Problem (continued)
Step Check Point
8 Is the head driver If you see the C380 Main board from the heat sink
transistor defective? side, the following four power transistors can be
found:
• Q3 and Q4: Outputs the common voltage for the
row A and B (black nozzle rows)
• Q5 and Q6: Outputs the common voltage for the
row C, D, and E (color nozzles)
To check if each pair transistor is working properly,
check the trapezoid waveform at the emittor terminal
of the charging side (Q3 and Q5). Check the
waveform while running a print.
NOTE: Frequency of waveform and voltage level
Revision A
Action
(p-p) varies if printing is performed through
the driver. Therefore, as long as the
trapezoid waveform is output, the head
driver IC is considered good, and the
printhead must be replaced in that case.
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