LG LAS855M Service Manual page 12

Smart hi-fi audio wireless multi-room sound bar

User manual (24 pages)

Simple manual (24 pages)

Table of Contents

ONE POINT REPAIR GUIDE ............................................................................................................................ 2-2

1. IF THERE IS NO SOUND OR HAVE A PROBLEM ON LCD. ............................................................... 2-2

2. IF THE SET DOESN'T BOOTING WHEN YOU TURN ON THE SET ................................................... 2-3

3. IF THE SET DOESN'T BOOTING WHEN YOU TURN ON THE SET ................................................... 2-4

4. IF THE SET DOESN'T BOOTING WHEN YOU TURN ON THE SET (LED DOES NOT TURN ON) ... 2-5

5. IF THE SET DOESN'T BOOTING WHEN YOU TURN ON THE SET. .................................................. 2-6

6. IF THERE IS NO SOUND. ...................................................................................................................... 2-7

7. IF THE SET DOESN'T BOOTING WHEN YOU TURN ON THE SET ................................................... 2-8

8. IF THE SET DOESN'T BOOTING WHEN YOU TURN ON THE SET (LED DOES NOT TURN ON) ... 2-9

9. NO SOUND FROM THE R ch SPEAKER. ........................................................................................... 2-10

10. NO SOUND FROM THE L ch SPEAKER. ............................................................................................ 2-11

11. IF NOT BOOTING WHEN YOU TURN ON THE SET. ......................................................................... 2-12

12. IF NOT BOOTING WHEN YOU TURN ON THE SET. ......................................................................... 2-13

13. IF NOT BOOTING WHEN YOU TURN ON THE SET. ......................................................................... 2-14

14. WIRED NETWORK CONNECTION ERROR. ...................................................................................... 2-15

15. PORTABLE FUNCTION DOESN'T WORKING .................................................................................... 2-16

16. OPTICAL FUNCTION DOESN'T WORKING ........................................................................................ 2-17

17. BLUETOOTH FUNCTION DOESN'T WORKING ................................................................................. 2-18

18. HDMI FUNCTION DOESN'T WORKING .............................................................................................. 2-19

19. Wi-Fi FUNCTION DOESN'T WORKING ............................................................................................... 2-20

20. WIRELESS WOOFER CONNECTION DOESN'T WORKING .............................................................. 2-21

ELECTRICAL TROUBLESHOOTING GUIDE ................................................................................................. 2-22

1. POWER / MICOM / LCD ....................................................................................................................... 2-22

2. Wi-Fi ...................................................................................................................................................... 2-23

3. AMP / PWM .......................................................................................................................................... 2-24

4. PAIRING BLUETOOTH ........................................................................................................................ 2-25

5. OPTICAL ............................................................................................................................................... 2-26

6. PORTABLE ........................................................................................................................................... 2-27

7. HDMI ..................................................................................................................................................... 2-28

WAVEFORMS OF MAJOR CHECK POINT .................................................................................................... 2-29

1. MPEG X-TAL ........................................................................................................................................ 2-29

2. PWM X-TAL .......................................................................................................................................... 2-29

3. MICOM (EEPROM) ............................................................................................................................... 2-30

4. MPEG .................................................................................................................................................... 2-30

WIRING DIAGRAM .......................................................................................................................................... 2-31

BLOCK DIAGRAMS ........................................................................................................................................ 2-33

1. SYSTEM BLOCK DIAGRAM ................................................................................................................ 2-33

2. POWER BLOCK DIAGRAM ................................................................................................................. 2-35

CIRCUIT DIAGRAMS ...................................................................................................................................... 2-37

1. MAIN - MICOM CIRCUIT DIAGRAM .................................................................................................... 2-37

2. MAIN - MPEG CIRCUIT DIAGRAM ...................................................................................................... 2-39

3. MAIN - MEMORY CIRCUIT DIAGRAM ................................................................................................ 2-41

4. MAIN - ADC & I/O CIRCUIT DIAGRAM ............................................................................................... 2-43

5. MAIN - DC-DC CIRCUIT DIAGRAM ..................................................................................................... 2-45

6. AMP - PWM CIRCUIT DIAGRAM ......................................................................................................... 2-47

7. AMP - AMP CIRCUIT DIAGRAM .......................................................................................................... 2-49

8. FRONT CIRCUIT DIAGRAM ................................................................................................................ 2-51

9. KEY CIRCUIT DIAGRAM ..................................................................................................................... 2-53

CIRCUIT VOLTAGE CHART ........................................................................................................................... 2-55

1. ICs ......................................................................................................................................................... 2-55

2. CAPACITORS ....................................................................................................................................... 2-55

PRINTED CIRCUIT BOARD DIAGRAMS ....................................................................................................... 2-57

1. MAIN P. C. BOARD DIAGRAM ............................................................................................................ 2-57

2. AMP P. C. BOARD DIAGRAM ............................................................................................................. 2-59

3. FRONT P. C. BOARD DIAGRAM ......................................................................................................... 2-59

4. KEY P. C. BOARD DIAGRAM .............................................................................................................. 2-59

SECTION 2 ELECTRICAL

CONTENTS

2-1

Table of Contents