Haier color TV 29FK1 indicator flashing no light silent maintenance example - appliance repair - Huaqiang Electronic Network
Brand model: Haier Color TV 29FK1
Symptom: The indicator light flashes, no display, and no sound.
Overhaul process: Initially, a short circuit was detected. The line pipe, line package, and line pipe were disconnected and found to be shorted. The previous technician had already replaced the line pipe. After disconnecting the load and testing B+ voltage, the power supply was normal. No obvious short circuit was found in the line package. The reverse process capacitor and correction capacitor were checked and appeared to be in good condition. The line test machine was replaced, and the start line was activated, but the line tube failed again immediately. No issues were found in the deflection section. It was suspected that the line package might be faulty. A new line package was installed, and the test machine showed high voltage with picture and characters. However, when adjusting the acceleration and focus, it was found that the acceleration voltage was unstable, fluctuating between high and low levels, similar to a problem with the acceleration adjustment potentiometer.
At this point, I suspected the line package might still be problematic, even though it was a new one. Further checks revealed that the ABL voltage was not at 0V. While adjusting the acceleration potentiometer, I noticed that the ABL resistor R640 (1KΩ) started smoking. I replaced it, as well as VD641, which had been damaged. After replacing these components, the acceleration and focus adjustments returned to normal, and the color TV was successfully repaired. This case highlights how sometimes even after replacing parts, further investigation is needed to identify secondary faults that could affect overall performance.
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