Epson LQ-1170 - Page 104

Table 5-4. Repair of the Power SUDDIY Board (Continued)
Condition
The voltage at +
5V
line is dead.
Cause
The
+35V line is
dead.
ICI is dead.
D24 is dead.
Checkpoint
Check the
+35V line.
Check the oscillation waveform (IC21, pin
5) and the switching waveform (IC21, pin
3).
Check the output waveform.
Action
Replace IC21.
Replace
D24.
5-15