Service manual

Page 22 of 64
4-2-6 Video-Block
OK
OK
NG
VIDEO、S-VIDEO、Y/Cb/Cr
Mode no display
Check power switch is in “Power ON”
status, and check DC POWER block.
Disconnect the signal cable. Is the
screen show “Searching”?
Connect the signal cable
1.AV mode:
Measure C4 input waveform
at U1.
2.S-VIDEO mode:
Measure C4 and C3 input
waveform at U1.
3.YCbCr mode:
Measure C18/C19/C20 input
waveform atU1.
Check U6(PW1231) circuit
Check U1
OK
OK
Check relevant circuit whether have
short or open, and check the signal
cable whether normal.
(Please use the Color-bar signal to
check）
Check relevant circuit whether have short or
open(and check CLK/SYNC, relevant circuit
between U1 to U20)
NG
OK
Check the SCALAR and
LVDS circuit.
NG
Check relevant circuit whether have short or
open(and check CLK/SYNC, relevant circuit
between U1 to U20)
X1
U1
U6
X5
Same
above