Phillips 42PFL6704D/F7 Issue

[jkread]

Make: Phillips
Model: 42PFL6704D/F7
Issue: After a short time running the screen goes black but the sound continues to play. It doesn't appear to be the backlight as no screen image can be seen from any angle close up. If turned off for a while it will come back on with and repeat the same process. I've attached images of the two main board. I don't see anything straight away but I've never really done this so don't know exactly what to look for.

Thanks for any help or suggestions, I'm new to this, just want to get my TV back work. If I did anything wrong or need to provide more infor kindly let me know.

Thanks,
John

[philliesfan30m]

Re: Phillips 42PFL6704D/F7 Issue

it more than likely is a backlight issue. you need a really bright light to shine on the screen to see the picture not just by getting close and looking. when it does run for a short time does the picture show up at all?

[philliesfan30m]

Re: Phillips 42PFL6704D/F7 Issue

can you take a picture of the whole back of the tv?

[jkread]

Re: Phillips 42PFL6704D/F7 Issue

Works perfectly for 10-15 minutes maybe longer the first time after its been off for a few hours. I've attached a picture of the whole back but might need to lay it down again to get a better picture. I'm running it now and assuming reconnecting all the cables inside doesn't fix it (not at all hopeful) I've got a spot light standing by. None of the boards show any burns or discoloration beyond the normal where they soldered it.

Thanks so much for helping out.

John

[philliesfan30m]

Re: Phillips 42PFL6704D/F7 Issue

i'm just guessing but it might be a cold solder joint somewhere on the cold side of the board. can you post a good pic of the bottom of the power board? i would probably just reflow the solder on the inverter section and see if it changes.

[philliesfan30m]

Re: Phillips 42PFL6704D/F7 Issue

do you have a can of compressed air? it is a heat fault somewhere and when the tv screen goes black i would try cooling down some of the components and see if the picture comes back and if it does you will know what component is giving you the problem. maybe someone else could chime in and give their opinion.

[jkread]

Re: Phillips 42PFL6704D/F7 Issue

That makes a lot of sense. I've been running it with the back off for several hours now with no issue. I'll take the board off tomorrow and look it over closer and post pictures of the back. Thanks again.

[jkread]

Re: Phillips 42PFL6704D/F7 Issue

Sorry. My girlfriend interrupted my priorities yesterday. Here is a pic of the back of the power board. Nothing obvious to this untrained eye. No luck getting it to have the issue with the back off to allow a cooling with air.

John

[jkread]

Re: Phillips 42PFL6704D/F7 Issue

So far so good. I reinstalled the back and have run the set at least a few hours the last couple days with no issues. No idea what happened but I'll cross my fingers and hope it keeps working till I sell a house and can afford to replace it.