Sharp LC-32WD1E/S/RU Service Manual page 35

LC-32WD1E/S/RU, LC-37WD1E/S/RU, LC-42WD1E/S/RU, and LC-32/37/42WT1E
NO picture on display via tuner reception (analog TV)
No picture appears on LCD screen during tuner reception
Checklist:
1) Is "INPUT SOURCE" button
2) Is MENU-PICTURE-Contrast/Brightness set to "MIN" ? ==> Set it to appropriate level
3) Is ANT-CABLE disconnected or connected improperly? ==> Connect it correctly as per the operation manual
Is level of tuner supply voltage (pin 7 of tuner U011) 5V ?
Is level of I2C lines (pins 4 and 5 of tuner U011) LOW ?
Is level of tuner AGC (pin2 of U011) 0V ?
Is the video signal (IF) sent from pin8 of tuner (U011) ?
Is video signal sent from pins 4 and 5 of video SAW filter (Z011)
Is TDA15134E (D013) UOCV_DVCLK clock there
AND are the UOCV_DV(x) signals toggling?
are UOCV_DV(x) and UOCV_DVCLK signals arriving to
the CPLD (D080) (XC2C128-7TQG144C) ?
GOTO VIDEO PATH CHECK
on the remote control set up correctly ? ==> See operation manual and set "INPUT SOURCE" to "TV"
yes
yes
no
no
yes
yes
yes
yes
Check if D0911 (LD1117DT50) output (pin2) is 5V
IF yes, check if D0918 (MC34063A) output (pin2) is 6v6
no
IF yes, check +12V_DVB
These are I2c communication lines for tuner control.
Follow the path and check whether they are forced to LOW.
yes
Check I2C switch D016
Check analog switch D0111 (74HCT1G66PW)
yes power supply (5V) and functionality
Check the tuner (U011) and peripheral circuits
no
check video SAW filter and peripheral circuits
check SAW_SW signal
no
TDA15134E (UOCV) (D013) is not functioning normal,
no check GTV SW and peripherals (power supply,xtal,...) of D013
check resistor networks on UOCV_DV signals
no
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