LG OM7550 Service Manual

3-33
ELECTRICAL TROUBLESHOOTING GUIDE
B
Check speaker cable connection.
Check IC202.
Check IC700.
Check IC204.
Check SMPS.
Check Q705, Q706.
Check IC202.
Check IC701, IC705.
Check IC204, IC205.
Check SMPS.
Check Q707, Q708, Q717, Q718.
pin49, 50 of IC202,
FRONT signal OK?
pin13 of IC700
FRONT audio signal OK?
IC204 FRONT
audio signal OK?
±66 V, -B+12 V, ±5 V
Power voltage OK?
Q705,Q706
OK?
pin45~48 of IC202,
MID or SW signal OK?
pin13 of
IC701, IC705 MID or SW
audio signal OK?
IC204, IC205
MID or SW
audio signal OK?
±66 V, -B+12 V, ±5 V
Power voltage OK?
Q707, Q708,
Q717, Q718 OK?
NO
NO
NO
NO
NO
NO
NO
NO
NO
NO
YES
YES
YES
YES
YES
YES
YES
YES
YES
YES
OK

LG OM7550 Specifications

General

Brand	LG
Model	OM7550
Category	Stereo System
Language	English