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yesterday repair a Samsung UA32EH5080R sound power flashlight backlight is not lit all the shadow image search key backlight LED open circuit of this machine is found and a backlight power supply through one board see Board traces found that the power board has three voltage outputs Dm853 and DM854 are 13V and 5V rectifier output measurement The middle of the two diodes are normal voltage and then measure the dm851 dm852 rectifier output voltage of the two diodes Digital Multimeter Has been beating has been unable to properly display the number and then the two diodes in series behind the inductor and another diode D9101 voltage 240V so that the voltage is normal and then check other components for a long time has not found the problem Finally want to give up maintenance Direct buy board for nothing today and then picked up the study wanted to go is unable to figure out why the measurement dm851 dm852 The two diode rectifier output voltage has been beating Why is incomplete rectification before the online measurement of these two diodes No problem now again Open the two diodes side of the foot measurement or good after demolition That 200V 47uf capacitor filter capacitor removed to break off a foot do not know when it is disassembled or broken inside the previous and then find a 400V 47uf capacitor put on a long boot back to the machine came this machine Most of the luck to repair the current analysis should be before this capacitor is broken inside the rectifier filter is not completed so the backlight circuit does not work Remind counterparts do not think capacitor is not leak it is good or bad
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