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3-39
3-40
CIRCUIT DIAGRAMS
1. SMPS 1 CIRCUIT DIAGRAM
A
B
C
D
E
F
G
H
I
J
K
L
M
N
O
P
Q
R
S
T
RH300'S
No Power
BD101,R101 is Defective
FD(+)FD(-) No Power
D121 is Defective
-28VA No Power
D122 is Defective
14VA No Power
D125 is Defective
No Power
D102 is Defective
3.8VA No Power
D127 is Defective
5V No Power
D125 is Defective
5.6VA No Power
D123 is Defective
S/W Error
IC101 is Defective
Switching Error
IC102,IC103 are Defective
No Power
F101 is Defective
5.3VA No Power
D128 is Defective
5V No Power
IC155 is Defective
5V No Power
IC156 is Defective
Copyright © 2008 LG Electronics. Inc. All right reserved.
Only for training and service purposes
LGE Internal Use Only
WHEN SERVICING THIS CHASSIS, UNDER NO CIR-
CUMSTANCES SHOULD THE ORIGINAL DESIGN BE
MODIFIED OR ALTERED WITHOUT PERMISSION
FROM THE LG CORPORATION. ALL COMPONENTS
SHOULD BE REPLACED ONLY WITH TYPES IDENTI-
CAL TO THOSE IN THE ORIGINAL CIRCUIT. SPECIAL
COMPONENTS ARE SHADED ON THE SCHEMATIC
FOR EASY IDENTIFICATION. THIS CIRCUIT DIAGRAM
MAY OCCASIONALLY DIFFER FROM THE ACTUAL
CIRCUIT USED. THIS WAY, IMPLEMENTATION OF THE
LATEST SAFETY AND PERFORMANCE IMPROVE-
MENT CHANGES INTO THE SET IS NOT DELAYED
UNTIL THE NEW SERVICE LITERATURE IS PRINTED.
1. Shaded( ) parts are critical for safety. Replace only
with specified part number.
2. Voltages are DC-measured with a digital voltmeter dur-
ing Play mode.
IMPORTANT SAFETY
NOTE :