I just fixed this Poloroid FLM-3701 TV after it sat on my bench for a week, and thought my experience (which I have repeated several times) would serve as a good lesson for newbies: Never assume a cap is good just because it looks fine. I've gotten caught several times here and it still gets me sometimes LOL.
All the large filter caps on the outputs had visibly failed. I replaced them all. TV Still did not come up, so I checked the rails. No voltage on any of them. SOoooo, I checked the 120V input, no problems with that. Checked the bridge and large 400V filter cap, no problems. I had a good ~80 Volts after the bridge and filter caps, but Nothing on ANY outputs.
So I got out my ESR tester and tested every cap on the board. One of the small 22uF 50V caps had a high ESR. I replaced it and viola! The TV powered on.
So, the lesson I've learned yet again is to ALWAYS TEST ALL the electrolytic caps!!!
Just thought I'd throw that out there; hope it helps someone.
All the large filter caps on the outputs had visibly failed. I replaced them all. TV Still did not come up, so I checked the rails. No voltage on any of them. SOoooo, I checked the 120V input, no problems with that. Checked the bridge and large 400V filter cap, no problems. I had a good ~80 Volts after the bridge and filter caps, but Nothing on ANY outputs.
So I got out my ESR tester and tested every cap on the board. One of the small 22uF 50V caps had a high ESR. I replaced it and viola! The TV powered on.
So, the lesson I've learned yet again is to ALWAYS TEST ALL the electrolytic caps!!!
Just thought I'd throw that out there; hope it helps someone.
Comment