Checking method:
1. Check the signal strength or check whether the screen is normal when the external device is connected.
2. After measuring each voltage from power supply, finally replace the MAIN BOARD.
Standard Repair Process Detail Technical Manual
TUNER checking part
A. Video error_Video error, video lag/stop
<ALL MODELS>
A5
Established
date
Revised
date
Error
symptom
Content
A5
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Summary of Contents for 75SJ857A
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