LG DP381B Service Manual page 25

MAIN ELECTRICAL TROUBLESHOOTING GUIDE
B
YES
Normal
Audio output when
disc playback.
YES
Normal
IR. VFD & Front pannel
key functions.
YES
TEST END
LGE Internal Use Only
Proper
NO
Aout_L, Aout_R signal
on MT1389P
Check Audio filter,
amplify, mute circuit.
Commu-
nications between
NO
IR.VFD Front pannel key &
MT1389P & Front µ-com
is normally.
NO
Check the cable connection
on Front pannel.
3-16
NO
NO
YES
NO
YES
Copyright © 2008 LG Electronics. Inc. All right reserved.
Check Aout_L related circuit
Aout_R
Check the related circuit of
Audio DAC.
Check communication
lines on MT1389P
Only for training and service purposes