Toshiba 15DV703R, Service Manual

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Video problem
Check panel power on LVDS cable:
CN12 pin 1, 2,3,4,5 should have 5Vdc
(15”/19”/22”), CN13 Pin 27,28,29,30
should have 12V (26”/32”)
Check backlight on/off control:
CN1 pin2 should be 2~3.3Vdc
Video problem
Is OSD on the
screen?
No
Yes
Check if signal cable
is connected and has
signal output.
Which input has no picture?
Check tuner if
there is signal
to scaler, I2C,
power and
related circuit.
Check signal
path from
connector to
scaler.
Check signal
path from
connector to
scaler.
Check signal path
from connector to
scaler, especially
the Y signal.
Check signal
path from
connector to
scaler.
RF AV VGA Component HDMI
1. Check TM2 #2,6 for the 5V
2. Check TM2 #4,5 for I2C check
Check C154
1. Check C172 for VGA_R
2. Check C174 for VGA_G
3. Check C176 for VGA_B
4. Check R91 for HSYNC
5. Check R93 for VSYNC
1. Check C168 for Y
2. Check C170 for Pr
3. Check C167 for Pb
1. Check HDMI SW (IC5)
input and output TMDS
signal.
2. Record equipment part
number for easy duplicate.