LG 47LA7400 Service Manual page 118

Standard Repair Process Detail Technical Manual
symptom
LCD TV
Content
<ALL MODELS>
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.
Copyright ⓒ 2013 LG Electronics. Inc. All right reserved.
Only for training and service purposes
Error
C. Audio error_No audio/Normal video
Voltage and speaker checking method
when there is no audio
(Power Board ↔ Main Board) -
24 Pin
SMAW200-H18S1 (YEONHO)
②
1 Power on
3 3.5V
5 3.5V
②
7 GND
9
11 GND
13
15
17 GND
19 GND
21 GND
23 L/DIM0_MOSI
2 INV_ON
4 PDIM #1(PWM Dim #1)
6 PDIM #2(PWM Dim #2)
8 GND
24V 10 24V
12 GND
12V 14 12V
12V 16 12V
18 GND
20 GND
22 L/DIM0_VS
24 L/DIM0_SCLK
- 72/83 -
Established
2012. 11 .30
date
Revised
date
공통
①
③
A25
LGE Internal Use Only