Philips SDV434/19, Service Manual

Page: 13 / 44

4-3
All output voltages on the power board is 0V or deviated.
No
No
No
Yes
No
U1(PIN 8 - Drain waveform)
Replace F1
Replace C4 if D1, D2, D3, D4 are
normal.
Check/ replace U1.
Check whether U1 are eroded.
All output voltages on
the power board is 0V or
deviated
Check whether there is
300V on C4.
Check whether 100KHz
oscillating signal on
Pin6 of U1
Check if +5V, +3.3v, +12V,
-12V and -24V are short.
Check whether the components in the
short-circuit voltage are defected or eroded.
Yes
Yes
Yes
Yes
U1(PIN 3 - RC waveform)
Trouble shooting chart
Check whether
F1 is blown