Amp Abnormal - LG MCD206 Service Manual

ELECTRICAL TROUBLESHOOTING GUIDE

2. AMP ABNORMAL

AMP abnormal
YES
YES
Check L701,702
pin2, 4 output signal.
NO
Check U701 YES
pin28,31,36,39 PWM
output signal.
NO
YES
Check U701
pin7,17 high.
NO
Check R725, U701.
Check the speakers
connection.
Check
L703,L704,L705,L706,
C711,C712.
Check U701
YES
pin6,8,16,18 whether
PWM signal.
NO
Check
YES
U601pin70,71,74,75
PWM signal.
NO
YES
Check U601
pin86,87 signal.
NO
Check FB600, U601.
3-4
Check U701
YES
pin44,21,22,23,26,27,
32,35,40,41 whether
12V & 22V.
NO
Check power.
Check
R721,R722,R724,R726.
Check U601
YES
pin19 "DAC_CK",
pin20 "DAC_RCK",
pin23 "DAC_DATA"
data signal.
NO
YES
Check U601, U602.
Check U701
pin2,5 data signal.
NO
Check R727.
Normal.
YES
Check U601
pin78 "PWM_DATA",
pin79 "PWM_CLK",
pin96 "PWM_RESET"
data signal.
NO
Check U802.