Vizio VP50HDTV10A Service Manual page 37

PDP DISPLAY NOTHING(Digital 2 U35 with PORT B without screen)
BLOCK 1
Is picture on screen?
Is picture on screen?
Is picture color ok?
CONFIDENTIAL – DO NOT COPY
No
Check input source?
Yes
No
Check U37 I2C bus
SCL Pin 6
SDA pin 5
Check U35 pin 90 high
No
No
V sync R419
H sync R420
clock R421
No
Check Q44
source high(3.3V)
Yes
No
Check U35 I2C bus
CSDA pin 39
CSCL pin 40
Yes
Yes
Check U35 all power
Check U35's RGB data bus
No
B RP10,RP11
G RP12,RP14
R RP16,RP17
No
Check U37 power Check D66 and D65
5V Pin 8 Are there 5V output?
Yes
Check +3.3V_SW
Check crystal
FB19,FB20,FB21,FB22
Y2=28.322MHz
U41 +1.8V_HDMI1
Yes
No
Check Q44
Gata high(5V) Q44 fail
No
I2C addr. R424 Check Block 2
U35 fail
No
D66 fail
or
D65 fail
14
Page 9-18
File No. SG-0219