LG SPM2 - Section 3 Electrical

3-1
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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, STANDBY LED DOESN’T WORK ........................ 3-4
2. NO SOUND ............................................................................................................................................. 3-7
3. PROTECTION ERROR ......................................................................................................................... 3-11
4. LED DOESN’T WORK .......................................................................................................................... 3-13
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. SMPS P. C. BOARD DIAGRAM ........................................................................................................... 3-19
2. MAIN P. C. BOARD DIAGRAM ............................................................................................................ 3-21
3. LED P. C. BOARD DIAGRAM .............................................................................................................. 3-23
4. IR P. C. BOARD DIAGRAM .................................................................................................................. 3-23
5. KEY P. C. BOARD DIAGRAM .............................................................................................................. 3-25