3-2
Copyright © 2018 LG Electronics Inc. All rights reserved.
Only for training and service purposes.
ONE POINT REPAIR GUIDE
1. NO POWER
If the unit doesn’t work by no power problem, repair the set according to the following guide.
1-1. FUSE/ THERMISTOR/ BRIDGE DIODE
1-1-1. Solution
Please check and replace F901, TH901 or TH903, BD901 on SMPS board.
1-1-2. How to troubleshoot (Countermeasure)
1) Check if the fuse F901 is open or short-circuit.
2) Check if the NTC thermistor TH900 or TH903 is normal or open.
3) Check if the bridge diode BD901 is short-circuit by over current with a digital multi-meter.
1-1-3. Service hint (Any picture/ Remark)
< F901 >
If F901 is not short-circuit,
replace it with a same
speci
fi
cations one.
< BD901 >
If BD901 is short-circuit,
replace it with a new one.
<TH901 or TH903 >
If TH901 or TH903 is open,
replace it with a new one.
L2
L1
L2
L1
L2
L1
L2
L1
(5A 250V)
T5AL/250V
CY900
VR901
SVC681-14
1
0
9
H
F
1
2
FH902
1
2
CY901
GND
PN901
GP390-02P-TS
CM901
100nF/275VAC
R900
1.5M
CM902
100nF/275VAC
LF901-*1
1
2
3
4
TH903
TH901
DSC 3D-15 MSFC
CY902
TH902
HS900
1
2
3
4
OTW1
1
2
OTW2
1
2
OTW3
1
2
OTW4
1
2
BD901
RBU605M
1
2
3
4
C903-*2
180uF
C903-*3
270uF
C903-*1
330uF
LF901
1
2
3
4
LF902
1
2
3
4
LF902-*1
1
2
3
4
F901
C903
330uF
450V
R901
470K
R902
470K
R903
470K
Y_GND
TP901
TP902
F901-*1
!
!
!
!
!
!
!
!
T8AL/250V
!
NUTRAL
(WH/BL)
LIVE
(BK/BN)
!