Smps/Panel Backlight - Samsung QN65Q8CAMP Service Manual

4. Troubleshooting

4-1-3. SMPS/PANEL BACKLIGHT

1. Activate Backlights Test
TV Screen for active backlight LEDs.
9
2. If No BACKLIGHTS
All Vdrv to LD from SMPS for approx 75 VDC with meter.
9
• If any missing or wrong voltages remove (LD Board :
Check ALL Vdrv on the SMPS Connector
9
• If any Vdrv is still missing or wrong at SMPS, replace SMPS.
• If Vdrv is restored on SMPS replace LD Board.
3. If BACKLIGHTS ON BUT A PANEL SECTION(S) OFF
- SIMPLE BL ERROR TEST
Check each panel ribbon configuration.
9
• If any have a different number of pins or a different pin or drive configuration
go to additional backlight test.
4-4
<LD Board>
CNV904 (Back Light)
1 GND 2
3 B13V 4
5 GND 6
7 Vdrv 8
9 Vdrv 10
11 Vdrv 12
13 GND 14
: – Disconnect Lead Cable from Main to Power Supply.
CN903
:
SIMPLE BL TEST : Can Swap Panel Connector
(ONLY When exactly the same pin
CNV904
GND 1
FAULT 3
GND 5
Vdrv 7
Vdrv 9
Vdrv 11
GND 13
CNV904 ) LD connector to SMPS and retest.
config.)
CN903
<SMPS Board>
CN903
GND 2 GND
Vdrv 4 Vdrv
Vdrv 6 Vdrv
Vdrv 8 Vdrv
GND 10 GND
B13V 12 Fault
GND 14 GND
do not perform this simple test