I don't believe it as most of the time it will surely work as this is a The Monitor has the same symptom again which is display shutdown after few seconds! Guess what? Fresh solder was applied to the high voltage transformer pins and I'm ready to "On" the LCD Monitor. Both the tuning capacitors found to be okay but there were dry joints in the transformer pins.
In this case, as usual after I have confirmed that only two C5707 transistors shorted, I began to test the tuning capacitors and check the pins of the high voltage transformer. I had come across quite a number of shorted C5707 transistors caused by dry joints in pins of the high voltage transformer. You also have to observe the high voltage transformer pins carefully. The reason why I emphasis on checking this tuning capacitors was because the capacitors have a high failure rate that could cause the C5707 transistor to go shorted.
However, from my experience, checking only the capacitance value doesn't guarantee that the capacitor is good unless you confirm it with ESR meter. If you do not own one, you can use the digital capacitance meter to check the capacitance value. Besides the shorted transistor, one also has to check the tuning capacitor for high ESR value with the help of ESR meter. The cause of the problem was usually a shorted one or two of the C5707 push pull transistors. This BenQ T705 LCD Monitor has a common fault of display shutdown after few you "On" for few seconds.
In this case, as usual after I have confirmed that only two C5707 transistors shorted, I began to test the tuning capacitors and check the pins of the high voltage transformer. I had come across quite a number of shorted C5707 transistors caused by dry joints in pins of the high voltage transformer. You also have to observe the high voltage transformer pins carefully. The reason why I emphasis on checking this tuning capacitors was because the capacitors have a high failure rate that could cause the C5707 transistor to go shorted.
However, from my experience, checking only the capacitance value doesn't guarantee that the capacitor is good unless you confirm it with ESR meter. If you do not own one, you can use the digital capacitance meter to check the capacitance value. Besides the shorted transistor, one also has to check the tuning capacitor for high ESR value with the help of ESR meter. The cause of the problem was usually a shorted one or two of the C5707 push pull transistors. This BenQ T705 LCD Monitor has a common fault of display shutdown after few you "On" for few seconds.
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