Samsung QE49Q8 Series, Руководство по обслуживанию

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4-2-1. TV POWER STANDBY TEST
1. Power TV On
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POWER ON .2Vdc (when off) changes to 3.3Vdc (on)
• Note: Will stay On for short time when powered off.
2. If voltage error or no change:
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Jog Function & IR Control Test
3. If OK replace Main Board:
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All 13V supplies for approx. 12.7VDC
4. If any wrong voltages, remove SMPS connector to Main Board:
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All A13V again for 12.7VDC
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All Vamp supplies for approx. 18 VDC
5. If OK replace Main Board:
6. If still wrong voltage replace SMPS:
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OVD_LEVEL (Over Voltage Detect) 3.3Vdc : Operating Normal
7. If 0V or changing, an SMPS or Panel error exists. Perform Backlight Test.
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Backlight On/Off : OV Off to 4.4Vdc On- If missing or error : Replace Main Board.
8. Backlight ON
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Backlight On/Off 0V Off to 3.4Vdc ON (LD Board CN9003A)
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Vdrv supplies to LD Board (approx 78V dc with multi meter)
4-2-2. SMPS/PANEL BACKLIGHT TEST
1. 1. Activate Backlig hts Test : Disconnect Lead Cable from Main to Power supply.
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TV Screen for active backlight LEDs.
2. 2. If No BACKLIGHTS
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Minus(Control) pins & Plus(Supply) pins voltages on the Panel connector. (with fine test probe on left side of
connector only for safety)- If no pin voltages replace SMPS.
3. 3. If BACKLIGHTS ON BUT PANEL SECTION(S) OFF
• SIMPLE BL ERROR TEST:
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Check each panel ribbon configuration.
• If any have a different number of pins or a different pin or drive configuration do not perform this simple test go to
additional backlight test.
• If each have same number of pins and exact pin configuration.
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Verify exact Panel Backlight error location (dark vertical line)
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Turn off TV and Remove AC Power
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Swap the two adjacent panel ribbons in that area
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Reconnect AC Power and turn on the TV
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Check location of defect (dark vertical line)
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If the defect remained in the same location the panel is defective.
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If the defect moved to another location the LD Board is defective (NOTE: In rare cases the Main Board may be
defective since it provides Local dim control.
• BACKLIGHT DIMMING PROBLEMS
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Go to Menu > Picture > Expert Settings > Backlight and vary level (0 ~ 50)
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If no backlight changes observed :
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Panel Connector minus (-) pin voltages and ANA-DIM voltages CNM801 while changing backlight level.
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If minus(-) pin voltages don't change, and ANA-DIM changes, replace SMPS
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If ANA-DIM doesn't change replace Main Board.
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Use : MUTE > 4 > 1 > 9 > EXIT to test Panel Vertical Backlight Sections in normal operation mode.
4-4
4. Troubleshooting