Philips 27PT543S37A L01.1U AC-7638

18 years ago

I have a problem with my 2 year old Philips TV 27PT543S37A L01.1U AC-7638 not coming properly and appears to be similar to many other postings. I have read the many similar threads, however, I am so confused by related/non-related replies I am having difficulty pinpointing problem/resolution. I feel I need to post my own thread.

Problem: Power on TV, TV will make a humm/buzz/click noise for no more then 5 seconds and then the TV appears to go dead but the green power-on light stays on. It will stay like this indefinately. If I hit the up/down channel button one time it will click/buzz/humm again like its powering up then go dead again as before 5 seconds or less.

Workaround: However, if I continually press the channel up/down button it will no longer go dead after 5 seconds or less and the picture will slowly start to appear on screen, shrunken/garbled at first but slowly grow larger and clearer to fit screen until it looks like a normal picture after about 30 seconds. At this point the TV will run continuously without problem until the next time it is turned off. I also noted that if after running correctly for awhile and I shut off, then turn back on, the length of time I have to contually change channel to get picture is shorter then the 30 original seconds when cold. The length of time it takes for picture is exponential to the amount of time its benn since I turned off TV eventually going back to square one. So to me it appears when warm the picture comes on that much quicker.

I hope this clearly states the problem and not too much info. Sorry for the length. Any clear answers/help would be greatly appreciated.

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Comments (6)

koehler2u
18 years ago
I have spent the morning looking at threads with the same tv face down on the kitchen table. It too had the same problem.
I saw a thread for a 32" with the same mother board needed a cap.
I replaced the electrolitic capacitor at location 2455. It had began to fail from heat since it is located close to a couple of small transistors. It had not gone completly but the value was low.
I used an axial lead 47uf - 50 volt and with the longer leads. I think it will be further from the heat now.
Just watch the polarity when you change it out and use a low wattage iron.
TV fires up first time now.
bigern112
18 years ago
Thank you koehler2u i really appreciate it i was ready to start shooting my tv... The only thing i did different was use 47uf-35 volt. Again i really appreciate it. It worked Great
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fazi
15 years ago
I have Phillips 32" Tv, when i turn ON the Tv green LED turned ON but relay is keep clicking 4 to 5 times , then i have to turned OFF. I repeat this process for 15-20 times . then i heard buzzzzzzzzzzzzzzz ssssseeeennnneenenenene which indicates that picture will come soon. turn OFF and ON again it appear half size of the picture and turned OFF again, i repeat this process again 5-10 times the picture appear completely , after this no problem TV can run 24/7 i can change channel no problem . every time when i turn OFF the TV for a while i have to repeat the same hectic process , please advise me to rectify this problem
fazi
15 years ago
the capacitor 47uf-35 position 2455 looks in good condition.
fazi
15 years ago
any body help me plz
gnomeabram
14 years ago
I have the same TV with the same problem. I replaced the 47 uf 25 cap at 2455 with an axial 47uf50 as recomended earilier in this thread, and it didn't help.

For Fazi: Instead of doing that process 15-20 times, I simply place the TV on one of the empty input channels (ie. Front) before I turn it off, so that when I turn on the TV, it is on a channel with no signal (all black) and not using the built-in tuner. It never shuts off on this channel, as long as it is tuned to that channel on startup.

If you want to use the TV's built in tuner, leave it on "Front" for 2-3 minutes, then tune to the station. If you are using a VCR tuner or some other external tuner like a digital converter box, you have to leave it on the "Front" channel for only 15-30 seconds. At least that is my experience. I'd like to eliminate this problem altogether but it looks like I'll have to try something else other than the 2455 cap.

Philips 27PT543S37A L01.1U AC-7638

Comments (6)

koehler2u

bigern112

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