Samsung HG43NT678UF Service Manual page 59

4. Troubleshooting
„ BACKLIGHT DIMMING PROBLEMS
Enter Menu ?
1
If no backlight changes
are observed vary the
2
level again ?
NOTE
New is PWM1 Blue & PWM2 White that changes with backlight level (if Blue is 0V - "Yellow" if "white" 0V "Blue"
Backlight error would appear)
4-12
Go to Menu Picture
£
9
– vary level (0 – 50)
Check BLU_PWN (PIN 6) control voltages (CNM801)
9
– varies approx. 0.5V – 2.5Vdc
GND
1 2
A13V
3 4
A13V 6
5
A13V 8
7
A13V
9 10
GND
11 12
If it doesn't vary voltage ?
Replace MainBoard /
9
T-CON Board
Backlight
£
CNM801
ANA-DIM
OD ON/OFF
BLU_PWM
Power_On/Off
GND
GND
If it changes ?
Replace SMPS Board
9