LG SPP8-W

3-1
Copyright © 2021 LG Electronics Inc. All rights reserved.
Only for training and service purposes.
SECTION 3
ELECTRICAL
CONTENTS
WIRING DIAGRAM ............................................................................................................................................ 3-2
BLOCK DIAGRAM ............................................................................................................................................ 3-3
ONE POINT REPAIR GUIDE ............................................................................................................................ 3-4
1. NO BOOTING WHEN YOU TURN THE UNIT ON, NO MESSAGE OR “HELLO”
ON FRONT PANEL ................................................................................................................................. 3-4
2. NO SOUND ............................................................................................................................................. 3-7
3. PROTECTION ERROR ......................................................................................................................... 3-11
WAVEFORMS OF MAJOR CHECK POINT .................................................................................................... 3-14
1. CRYSTAL .............................................................................................................................................. 3-14
2. REMOTE CONTROL ............................................................................................................................ 3-15
3. OPTICAL ............................................................................................................................................... 3-16
CIRCUIT VOLTAGE CHART ........................................................................................................................... 3-17
PRINTED CIRCUIT BOARD DIAGRAMS ....................................................................................................... 3-19
1. MAIN P. C. BOARD DIAGRAM ............................................................................................................ 3-19
2. AMP P. C. BOARD DIAGRAM ............................................................................................................. 3-21
3. FRONT LED P. C. BOARD DIAGRAM ................................................................................................. 3-23
4. MIC & TOUCH P. C. BOARD DIAGRAM ............................................................................................. 3-23