Epson Stylus COLOR 760 Service Manual page 71

EPSON Stylus COLOR 760
Table 3-15. Cleaning does not Solve the Print Problem (continued)
Step Check Point
9 Is the head driving If a trapezoid waveform is not output in the
pre-driver defective? previous step, check all the power transistors (Q3 -
Q4) for base waveform. Like the head transistor in
Step 8, the base terminal input the similar trapezoid
waveform from the pre driver IC, but any wave form
is not input at Emita terminal. Replace the Power
Transistor.
If the waveform are not output correctly on Base
terminal of each Power Transistor, replace the
IC10 or 11 on C298 Main Board.
Otherwise, replace the C298 Main Board.
Troubleshooting
Action
Overview
Revision C
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