LG DP450G Service Manual page 24

MAIN ELECTRICAL TROUBLESHOOTING GUIDE
B
YES
Normal
Audio output when
disc playback.
YES
Normal
IR. VFD & Front pannel
key functions.
YES
TEST END
Proper
NO
Aout_L, Aout_R signal
on MTK1389
YES
Check Audio filter, amplify,
mute circuit.
Commun-
ications between
NO
IR.VFD Front pannel key &
MT1389 & Front μ-com
is normally.
YES
Check the cable connection
on Front pannel.
3-17
NO
Check Aout_L
related circuit Aout_R
NO
Check the related circuit of
Audio DAC.
NO
Check communi cation lines
on MT1389