12V - LG 55UF6790 Service Manual

Standard Repair Process Detail Technical Manual
Error symptom
Content
<All Models>
Checking order when there is no audio
1.Check the contact condition of or 12V connector of Main Board
2. Measure the 12V 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.
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Only for training and service purposes
C. Audio error_No audio/Normal video
Voltage and speaker checking method
when there is no audio
1 RL_ON
②
3 GND

5 12V

7 12V
②
9 GND
11 INV_CTL 12 PWM_DIM1
Established
date
Revised
date
2 PWM_DIM2
①
4 12V
6 12V
8 12V
10 GND
③
A21
1 SPK_R-
2 SPK_R+
3 SPK_L-
4 SPK_L+
LGE Internal Use Only
A21