Service manual

4. Output power is unstable
Unstable power
Check sampling
Circuit
Check R810,
R811, R818
Change R810, R811,
R818
Check the R pin
voltage of IC803
about 2.5V
Check R809, R808, R814,
D809
Check D806, C815 if
short
Change
D806, C815
Check pin1 of
IC802 voltage
is 5.8V
Check pin3 of
IC802 voltage
about 1V
Change R801, R805,
R822, R823, R817
END
Check the C pin
voltage of IC803
if 3V
Change
IC803
41
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