3-12
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Only for training and service purposes.
ONE POINT REPAIR GUIDE
3. PROTECTION ERROR
No display or No Sound.
3-1. D(DC) PROTECTION
3-1-1. Solution
Replace MAIN board.
3-1-2. How to troubleshoot (Countermeasure)
1) Check DC Voltage of speaker out FL+/- (CN703 pin1, 2), FR +/- (CN704 pin1, 2, 3)
2) Check resistor crack, cold solder of ESS IC out [FL+(R570), FL-(R571), FR+(R572), FR-(R573)].
3) If ESS (IC501) out is ok and speaker out (FL+/-, FR+/-) has DC voltage replace MAIN board.
3-1-3. Service hint (Any picture / Remark)
< MAIN board top view >
MES
2
R3A1
R3A2
R3A3
F R 2 +
R3A4
R3A5
F R 2 -
R3A6
R5A5
R 7 A 1
F L 2 +
F L 2 -
R7C2
R7C3
C 5 A 1
C 5 A 2
F 3 0 0
F 3 0 1
C 7 C 5
C 7 C 6
Q 3 0 0
Q 3 0 1
Z D 5 0 4
L 3 0 2
K E Y _ G
L 7 0 9
L 7 1 0
FB303
JK300
F B 3 1 3
F B 5 0 7
R C F 5 0 0
F B 5 0 8
C N 5 0 5
R 5 2 8
C N 7 0 3
R338
C N 7 0 4
R339
C 3 0 0
C 3 0 1
C 3 0 7
C 5 0 3
C311
C 3 1 2
C 3 1 3
C315
C317
C 3 2 0
C 3 2 3
R365
R366
R380
R381
C347
C 3 4 8
R388
7
C 5 4 8
C 5 4 9
C355
C356
C 7 4 4
C 7 4 5
C 7 4 6
C747
D 3 0 0
C 7 5 8
C 7 5 9
R795
R796
R797
R798
C 3 7 8
C 3 7 9
D702
D703
C767
C768
IC302
I C 3 0 9
C771
C772
C773
C774
C 7 7 7
C390
C 7 7 8
C 7 7 9
C780
C783
C784
C785
C786
K E Y _ T P
R
L
S L 4 / S L 4 Y / S L 4 F M a i n
E A X 6 8 4 0 8 2 0 2 V e r 1 . 1
F R 4 - 4 L 1 . 2 T
2 0 1 8 . 1 2 . 0 6 2 6 1 X 6 7 . 5
CN703
CN703
CN704
CN704