Kangja after-sales service case: T2916N type TV, after turning on, it shows "three non" phenomenon but the power indicator light is on for 90 seconds. Note: The term "三无" (three non) in technical contexts often refers to a device having no picture, no sound, and no response upon startup. If further clarification is needed for your specific context, please let me know!

by doh40br30 on 2011-08-02 17:44:32

The Konka T2916N TV exhibits symptoms of no image, no sound, and no raster upon startup, but the power indicator light is on.

Analysis and Maintenance: The measured +B voltage is approximately 130V, indicating that the main power supply and CPU control are functioning normally. The voltage at pin 3 of XS402 is measured to be +200V, which suggests there is no abnormality in the line output circuit. Further measurements show that all voltages at the terminals of XS301 are 0V, causing the decoding circuit TA8759 to not output R, G, B signals. Upon checking the +12V power supply loop, no voltage is detected. It is found that the current-limiting resistor R408 in this circuit has become open-circuited.

Repair Method: Replace R408, and the fault is resolved.

Source: http://blog.sina.com.cn/kangjiadianshi