3-5
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C320
100nF
C321 10uF
/25V(L)
R329
1.5M NC
DGND
R320 33
C325
1uF C3D8
100nF
C342 10uF
/25V(L)
C3C8
100nF
12VA
C343 10uFNC
/25V(L)
R317 150K
R302
0OHM
C324
1uF
C3C9
100nF
R315
13K
(1%)
R314
390K
C322
10uF
R323 8.2K
C311
10uF
R316
100K
IC302
1
VIN
2
SW
3
GND4
BST
5
EN
6
FB
R322 62K
(1%)
DGND
D303
1
2
3
L303
10UH
DGND
5.1VA
DGND
C3D7
100nF
C326
10pF
FB308
VOUT = 0.798x(70.2K/13K+1)= 5.107V
[12VA to 5.1VA]
ONE POINT REPAIR GUIDE
NO BOOTING WHEN YOU TURN THE UNIT ON, NO MESSAGE OR “HELLO”
ON FRONT PANEL
When you turn on your set, it will blank / no message on front panel / doesn’t work.
1-2. IC302 System 5 V in Main Board (No 5.1 VA)
1-2-1. Solution
Replace MAIN board.
1-2-2. How to troubleshoot (Countermeasure)
1) Please check 5.1 VA of IC302 pin2 L303.
2) If 12 VA is OK, but 5.1 VA is abnormal at pin2 L303 of IC302 (VOUT), IC302 block has problem.
1-2-3. Service hint (Any picture / Remark)
< MAIN board top view >
IC302
L303
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