Additional Option Backlight Test - Samsung QN Q65FNF Series Service Manual

4-1-4. Additional Option Backlight Test

• 49 / 55 / 65 / 75 / 82 inches
1. Activate Backlights Test
TV Screen for active backlight LEDs.
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2. Locate LED 1 through LED 6 Diodes on SMPS
Check each stripe side of Diode for approx
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Check other side of Diode for approx
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• If any have low or missing 130V LED Drive
• If any have near 0V LED Control and 130V LED Drive is OK, Replace
3. Reconnect SMPS to Main/T-Con to Operate TV Normally
- Adjust backlights in Picture Test between 0 to 50 range
4. Locate LED 1 through LED 6 Diodes on SMPS
Check LED Control - non strip side of each Diode.
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Check that each vary from approx 70 Volts when at 0 setting to approximately 55 Vdc at 50 setting.
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• If it doesn't change, check
• If ANA-DIM changes replace SMPS
• It ANA-DIM doesn't change replace Main/T-Con Board
: Disconnect Lead Cable from Main to Power Supply.
130Vdc (LED Drive)
50Vdc (LED Control)
ANA-DIM changes (0.2Vdc to 0.7Vdc) on CNL801 .
check SMPS.
defective Panel
4. Troubleshooting
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