Re: PHILIPS 42PFL7404 no back-light



That cap is in the main line input rectifier....

Re: PHILIPS 42PFL7404 no back-light



But, when the back-light goes off all the other systems work; audio, tuner, IR remote, led signaling...And the error shown is: (Error code:17) -> back-light problem....

Re: PHILIPS 42PFL7404



These componentes are in the PS: IC953(TL431) and the opto PC901(NEC2561), but some other componentes round.

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These componentes are in the PS: IC953(TL431) and the opto PC901(NEC2561), but some other componentes round.

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Re: PHILIPS 42PFL7404 no back-light

Thanks for your answer. I have already checked those 4 HV capacitors and both appearance and value seem correct. These 4 caps according to the scheme are used in the out volt-current-arcs inverter supervision sub-circuits. I have seen PS with caps problems and the look of those capacitors was very bad, but...

My 12 years old TV set is a PHILIPS 42PFL7404, the PS is a DELTA DPS-298, and the LG panel is LC420WUF. Three weeks ago the screen starts blinking slightly and a minute later went black, but with audio. I desconected from the power line, power on again and in a few minutes the same problem. I removed the back cover and all the PS components look good. Power up again and the problem disappears, go into the service mode and find (Error code:17) and 11000 display hours. Put the cover again and the screen goes black in 2 minutes. Then check all capacitors, diodes and Mosfets, resoulder the main connections,...

I have a problem with the back-light on a 12-years-old PHILIPS 42PFL7404 TV with DELTA DPS-298 power supply. Screen time is 11000h. A month ago the image started to flicker slightly and after a minute it turned off, but keeping the audio. It was necessary to disconnect from the line to turn it on again, with the same symptoms (Error code:17). The PSU seems to have all the components and welds fine. For a while I ran it without the back cover and it held up well without shutting down. With a heat fan I looked for the susceptible area and found it in the return circuit and supervision of the power...

Re: New Members - please post your introductions here

I have retired this year. I studied industrial electronic engineering and have worked on it for more than 35 years. I also have a small electronic laboratory at home, where I do some development and repairs. I have repaired and restored cameras, and so far I have managed to maintain my audio, video, and household appliances by downloading the schematics and spending many hours on them. Now I have a lot of free time and since my 12-year-old PHILIPS PFL TV has broken, I have started to try to repair it. In most of the technical...