LG CM9530 - SECTION 3 ELECTRICAL

SECTION 3 ELECTRICAL
CONTENTS
ONE POINT REPAIR GUIDE ............................................................................................................................ 3-2
1. NO POWER ............................................................................................................................................ 3-2
2. NO BOOTING WHEN POWER ON THE SET ....................................................................................... 3-4
3. VFD IS NOT DISPLAYED WHEN POWER ON THE SET ..................................................................... 3-5
4. NO BOOTING IN CD/USB FUNCTION .................................................................................................. 3-6
5. NO OPERATION OF MD ..................................................................................................................... 3-10
6. NO SOUND .......................................................................................................................................... 3-15
7. AUDIO OUTPUT IS SMALL OR NO AUDIO OUTPUT ........................................................................ 3-22
8. NO POWER ON (STANDBY LED IS BLINKING) ................................................................................ 3-23
9. SPEAKER NO AUDIO .......................................................................................................................... 3-24
ELECTRICAL TROUBLESHOOTING GUIDE ................................................................................................ 3-25
1. POWER SUPPLY ON SMPS BOARD ................................................................................................. 3-25
2. SYSTEM PART .................................................................................................................................... 3-29
3. NO AUDIO PART ................................................................................................................................. 3-30
4. NO LIGHTING (FRONT/ WOOFER SPEAKER) .................................................................................. 3-34
WAVEFORMS OF MAJOR CHECK POINT ................................................................................................... 3-35
WIRING DIAGRAM ......................................................................................................................................... 3-39
BLOCK DIAGRAMS ........................................................................................................................................ 3-41
1. SMPS BLOCK DIAGRAM..................................................................................................................... 3-41
2. MAIN SYSTEM BLOCK DIAGRAM ...................................................................................................... 3-43
3. MAIN POWER BLOCK DIAGRAM ....................................................................................................... 3-45
CIRCUIT DIAGRAMS ...................................................................................................................................... 3-47
1. SMPS - POWER #1 CIRCUIT DIAGRAM ............................................................................................ 3-47
2. SMPS - POWER #2 CIRCUIT DIAGRAM ............................................................................................ 3-49
3. MAIN - MICOM CIRCUIT DIAGRAM .................................................................................................... 3-51
4. MAIN - CD DSP CIRCUIT DIAGRAM .................................................................................................. 3-53
5. MAIN - SERVO CIRCUIT DIAGRAM ................................................................................................... 3-55
6. MAIN - ADC/ PWM CIRCUIT DIAGRAM ............................................................................................. 3-57
7. MAIN - AMP CIRCUIT DIAGRAM ........................................................................................................ 3-59
8. VOLUME CIRCUIT DIAGRAM ............................................................................................................. 3-61
9. VFD CIRCUIT DIAGRAM ..................................................................................................................... 3-63
10. MIC CIRCUIT DIAGRAM ...................................................................................................................... 3-65
11. PORTABLE CIRCUIT DIAGRAM ......................................................................................................... 3-67
12. FRONT SPEAKER LED - DRIVER CIRCUIT DIAGRAM ..................................................................... 3-69
13. FRONT SPEAKER LED - SUB CIRCUIT DIAGRAM ........................................................................... 3-71
14. WOOFER SPEAKER LED - DRIVER CIRCUIT DIAGRAM ................................................................. 3-73
15. WOOFER SPEAKER LED - SUB CIRCUIT DIAGRAM ....................................................................... 3-75
CIRCUIT VOLTAGE CHART .......................................................................................................................... 3-77
PRINTED CIRCUIT BOARD DIAGRAMS ....................................................................................................... 3-79
1. SMPS P.C.BOARD ............................................................................................................................... 3-79
2. MAIN P.C.BOARD ................................................................................................................................ 3-83
3. VOLUME P.C.BOARD .......................................................................................................................... 3-87
4. VFD P.C.BOARD .................................................................................................................................. 3-91
5. MIC P.C.BOARD .................................................................................................................................. 3-93
6. PORTABLE P.C.BOARD ...................................................................................................................... 3-93
7. FRONT SPEAKER LED - DRIVER P.C.BOARD ................................................................................. 3-95
8. FRONT SPEAKER LED - SUB P.C.BOARD ........................................................................................ 3-95
9. WOOFER SPEAKER LED - DRIVER P.C.BOARD .............................................................................. 3-97
10. WOOFER SPEAKER LED - SUB P.C.BOARD .................................................................................... 3-97
3-1