LG LAS454B Service Manual page 50

WIRELESS SUBWOOFER PART
ONE POINT REPAIR GUIDE ............................................................................................................................ 4-2
1. NO POWER PROBLEM (PVDD) ............................................................................................................ 4-2
2. POWER ON ERROR .............................................................................................................................. 4-3
3. POWER ON ERROR .............................................................................................................................. 4-4
4. WIRELESS CONNECTION .................................................................................................................... 4-5
WAVEFORMS OF MAJOR CHECK POINT ...................................................................................................... 4-6
1. VOLTAGE ............................................................................................................................................... 4-6
2. AMP VOLTAGE ...................................................................................................................................... 4-7
3. PWM ....................................................................................................................................................... 4-8
4. LED ......................................................................................................................................................... 4-9
WIRING DIAGRAM .......................................................................................................................................... 4-11
BLOCK DIAGRAM .......................................................................................................................................... 4-13
CIRCUIT DIAGRAMS ...................................................................................................................................... 4-15
1. WOOFER SMPS CIRCUIT DIAGRAM ................................................................................................. 4-15
2. WOOFER AMP CIRCUIT DIAGRAM .................................................................................................... 4-17
3. WOOFER KEY CIRCUIT DIAGRAM .................................................................................................... 4-19
PRINTED CIRCUIT BOARD DIAGRAMS ....................................................................................................... 4-21
1. WOOFER SMPS P. C. BOARD ............................................................................................................ 4-21
2. WOOFER AMP P. C. BOARD .............................................................................................................. 4-23
3. WOOFER KEY P. C. BOARD ............................................................................................................... 4-23
SECTION 4
CONTENTS
4-1