3-9
Copyright © 2008 LG Electronics. Inc. All right reserved.
Only for training and service purposes
LGE Internal Use Only
NO
NO
YES
YES
Check connection between
1389P & audio AMP.
Check audio filter,
amplify, mute circuit.
NO
NO
YES
Check communication
lines on 1389P.
YES
YES
TEST END
Check the cable
connection on front panel.
Normal
audio output when
disc playback?
Audio
AMP received correct
data stream?
Commu-
nications between
IR.VFD front panel key &
1389P is normally?
Normal
IR.VFD & Front panel
key functions?
NO
Check the related
circuit of audio AMP.
Normal
audio AMP
out?
E