Epson Stylus 820 Service Manual page 88

Stylus Color IIs / Stylus 820
5.2 Unit-Repair - C160 Power Supply Board
This section describes how to repair the C160 power supply board and main board. The table below provides
various symptoms, likely causes, and check points. The checkpoints refer to waveforms, resistances, and other
values to check to evaluate the operation of each component.
Sympton Condition
Printer does not +35V line is
operate at all. dead.
+5V is dead.
Rev. A
Table5-3. Repair of the C160 PSB / PSE
Cause
F1 is open. Check the F1.
T1 is open. Check T1 coils using the tester.
Q1 is broken. Check the wave-form at the drain of Q1.
Q2 or Q3 is Check the wave-form at the drain
broken. of Q2 and Q3.
PC1 is Check the wave-form at 3-pin of PC1.
broken.
L4962 is Check the oscillation at 5-pin of IC51.
broken.
Check the output wave-form
at 7-pin of IC51.
Checkpoints
Replace Q2 or Q3.
Troubleshooting
Solution
Replace F1.
Replace T1.
Replace Q1.
Replace PC1.
Replace IC51.
Replace IC51.
5-3