4-2
4. Troubleshooting
4-1-1. No Power
Symptom
The LEDs on the front panel do not work when connecting the power cord.
The SMPS relay does not work when connecting the power cord.
The units appears to be dead.
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Major
checkpoints
The IP relay or the LEDs on the front panel does not work when connecting the power cord if the cables are
improperly connected or the Main Board or SMPS is not functioning. In this case, check the following:
Check the internal cable connection status inside the unit.
Check the fuses of each part.
Check the output voltage of SMPS.
Replace the Main Board.
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Diagnostics
1
Does proper DC A3.3V
appear at C1019, R1009?
Check a IC1002
Change a main PCB ass’y
No
No
Does proper DC 5V, 3.3V, 1.25V,
CORE_1.24V, CLS_1.8V appear
at C1008, C1016, C1073, R1037,
C1034, C1033?
LAMP off, power indicator
LED red color?
No
Yes
No
Does proper DC 13V appear at
pin9, 10, 11 of CN1001?
No
Yes
Yes
Check a connection a power cable.
Yes
A power is supplied to set?
Check a other function.
(No picture part)
Replace a lcd panel.
Change a Assy PCB Power.
Check a IC1004, IC1005, IC1010,
IC1009, IC1007, IC1006
Change a main PCB ass’y
1
1
1
No
Does proper B3.3VD appear at
BD2711 of T-con b’d?
Yes
Change the T-con b’d
Caution
Make sure to disconnect the power before working on the IP board.
Содержание LN52B750U1M
Страница 7: ...1 4 1 Precautions Memo ...
Страница 31: ...4 4 4 Troubleshooting WAVEFORMS 1 R G B Output Signal PC_R Signal PC_G Signal PC_B Signal ...
Страница 33: ...4 6 4 Troubleshooting WAVEFORMS 1 Signal of HDMI Data 2 Digital Output Data ...
Страница 37: ...4 10 4 Troubleshooting WAVEFORMS 1 AV_CVBS Output Signal ...
Страница 39: ...4 12 4 Troubleshooting WAVEFORMS 1 I2C Data 3 Speaker out ...
Страница 66: ...4 39 4 Troubleshooting 5 Press 0 6 Save latest BSP images to update folder in usb memory ...
Страница 67: ...4 40 4 Troubleshooting 7 Enter bbm usb after connecting usb memory 8 Press 1 ...
Страница 68: ...4 41 4 Troubleshooting 9 Enter u boot bin 10 Press x to return prompt menu ...
Страница 359: ...6 5 6 Wiring Diagram 6 2 Wiring Picture ...