LG UBK80 Service Manual page 18

DIGITAL DISPLAY & MEDIA TRAINING MASTER ......................................................................................... 3-2
1. DISTORTED PICTURE ........................................................................................................................... 3-2
2. NO PICTURE .......................................................................................................................................... 3-7
3. PICTURE COLOR ................................................................................................................................. 3-12
4. NOISE/AUDIO PROBLEMS .................................................................................................................. 3-14
5. MISCELLANEOUS ................................................................................................................................ 3-17
6. BLU-RAY PLAYER ............................................................................................................................... 3-26
ONE POINT REPAIR GUIDE .......................................................................................................................... 3-27
1. NO POWER PROBLEM ....................................................................................................................... 3-27
2. NO BOOTING WHEN YOU TURN THE UNIT ON, NO GREEN LED ON FRONT PANEL ................ 3-30
3. NO HDMI VIDEO / AUDIO OUTPUT .................................................................................................... 3-38
4. NO SOUND ........................................................................................................................................... 3-39
5. NETWORK CONNECTION ERROR..................................................................................................... 3-40
6. NO DETECTION ................................................................................................................................... 3-41
ELECTRICAL TROUBLESHOOTING GUIDE ................................................................................................. 3-42
1. POWER SUPPLY ON SMPS BOARD .................................................................................................. 3-42
2. POWER SUPPLY ON MAIN BOARD ................................................................................................... 3-44
WAVEFORMS OF MAJOR CHECK POINT .................................................................................................... 3-50
1. SYSTEM PART - 1 ............................................................................................................................... 3-50
2. SYSTEM PART - 2 (SYSTEM MEMORY) ............................................................................................ 3-51
3. AUDIO PART (S/PDIF) ......................................................................................................................... 3-52
4. HDMI PART .......................................................................................................................................... 3-53
WIRING DIAGRAM .......................................................................................................................................... 3-54
BLOCK DIAGRAM .......................................................................................................................................... 3-55
CIRCUIT VOLTAGE CHART ........................................................................................................................... 3-57
PRINTED CIRCUIT BOARD DIAGRAMS ....................................................................................................... 3-59
1. SMPS P.C. BOARD .............................................................................................................................. 3-59
2. MAIN P.C. BOARD ............................................................................................................................... 3-61
3. LED P.C. BOARD ................................................................................................................................. 3-65
SECTION 3
ELECTRICAL
CONTENTS
3-1
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