LG 55LA7400 - Checking Order When There Is no Audio

24 Pin (Power Board ↔ Main Board) - 공통
SMAW200-H18S1 (YEONHO)
1
Power on
2
INV_ON
3
3.5V
4
PDIM #1(PWM Dim #1)
5
3.5V
6
PDIM #2(PWM Dim #2)
7
GND
8
GND
9
24V
10
24V
11
GND
12
GND
13 12V 14
12V
15 12V 16
12V
17 GND 18
GND
19 GND 20
GND
21 GND 22
L/DIM0_VS
23 L/DIM0_MOSI 24 L/DIM0_SCLK
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Checking order when there is no audio
① Check the contact condition of or 24V connector of Main Board
② Measure the 24V input voltage supplied from Power Board
(If there is no input voltage, remove and check the connector)
③ Connect the tester RX1 to the speaker terminal and if you hear the “Chik Chik” sound when you touch the GND
and output terminal, the speaker is normal.
Standard Repair Process Detail Technical Manual
Voltage and speaker checking method
when there is no audio
C. Audio error_No audio/Normal video
<ALL MODELS>
A25
Established
date
Revised
date
Error
symptom
Content
LCD TV
①
②
③
②
2012. 11 .30
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