Philips LCD 42PFL5432D/37 - Bad PSU

[trixter]

Re: Philips LCD 42PFL5432D/37 - Bad PSU

Working on the same case. Just opened the tv and the caps on psu were buldging. Same values as the ones posted in first thread. Once caps A,B,C, and D come in, I'll solder them in and see results. The tv is now doing that chirping sound with no screen. I've fixed quit a few things in my time. Hopefully I'll add this on to the list.

[Dizzer]

Re: Philips LCD 42PFL5432D/37 - Bad PSU

I too have the same exact problem as the TC. I have ordered the caps and will post my results upon installation of the new caps. For me, both caps B and D (based off the image in the first post) were bulging. I am replacing all of them just in case.

[nuklear]

Re: Philips LCD 42PFL5432D/37 - Bad PSU

well thanks to everyone that helped I figured out the wireing prob and broke the lcd screen while putting the back back on, so looks like its ment to stay broken

[nuklear]

Re: Philips LCD 42PFL5432D/37 - Bad PSU

hmmm... Resoldered it and now tv wont turn on? I just re ran the wires so i could put the back on and now it doesnt even have the standby light on again lol

[nuklear]

Re: Philips LCD 42PFL5432D/37 - Bad PSU

It worked! Thanks alot! Only thing now is I get a blinking/flashing from the tv. just to make sure, I used a power cord that had a 12v output is that ok to use? any ideas of why it would be flashing mybe every second would be great. Ok it stopped flashing mybe had to warm up? But again Thanks alot!!! saved alot of money and I appreciate it and so does my son!

[momaka]

Re: Philips LCD 42PFL5432D/37 - Bad PSU

Is this something I can do with having no experience in doing this kind of repair?

Most likely yes.
The wiring part is pretty straightforward - it's like putting new batteries in your remote. The only difference is there is some soldering involved (think of it as if the batteries had wires that you needed to connect). If you've never done any soldering before, that's the only part of this job that might make it a bit more challenging. But soldering is not all that hard. I've seen a quite a few people here come with no experience and recap their monitors. Just read the FAQs or see some videos on YouTube on how to solder.
Also:
1) make sure your soldering iron nice and hot before you solder/desolder
2) put a little solder on the tip of the iron before soldering/desodering components - this will allow for better heat transfer
3) don't be afraid that you might "burn" the board - keeping the iron on the board for up to 5-8 seconds is acceptable. It's much worse to try to remove or solder a component when you're not heating it enough.

----
What you need to do for this repair is:
1) desolder/remove jumper wire J5 and resistor R974 from the board.
2) take the (+) wire from the 12v external PSU and connect it to any of the two pins circled in red in the picture above.
3) take the (-) wire from the 12v external PSU and connect it to any of the two pins circled in black (this is also the ground of the power supply).
4) remove any loose solder from the board

Now the question is, have you found a 12v adapter/power supply yet?
If you want, you can just temporarily use a computer PSU to see if the TV will come on. On a computer PSU, 12v is carried by the yellow wires. The black wires are ground.

Again, the only downside of this mod is that it won't look too pretty, mainly because you will need to have both the external power supply and the TV plugged in order for the TV to work. And if you don't have an external power supply yet, it's probably a better idea to buy a new PSU for the monitor than to waste money on buying an external power supply.

[nuklear]

Re: Philips LCD 42PFL5432D/37 - Bad PSU

so where do I get this psu to put onto this board? Is this something I can do with having no experience in doing this kind of repair?

[momaka]

Re: Philips LCD 42PFL5432D/37 - Bad PSU

So the Standby supply is 12V.

I concur.
The other clue that gives this away is that there's only 2 transformers in this power supply (one of them being the broken one you mentioned) and each has a single output only.

So what's next?...
Remove J5 and R974. This will disable the primary side of the standby circuit. Then finally wire in 12v from an external power supply (see attached image below). Note that ground (GND) from the external PSU also needs to be connected.
I suggest a PSU capable of at least 2A. Also if there's any loose solder like in the pictures you posted, make sure to clean it up.

[PlainBill]

Re: Philips LCD 42PFL5432D/37 - Bad PSU

ok this might be it.

It's hard to tell when working with fragments of schematics, but there are clues. Notice that the defective transformer is T904. T904 is the transformer for the 12V output. The STANDBY line is coming from the main board, and controls the SMPS controller for the 24V supply. So the Standby supply is 12V.

PlainBill

[nuklear]

Re: Philips LCD 42PFL5432D/37 - Bad PSU

ok this might be it.

[PlainBill]

Re: Philips LCD 42PFL5432D/37 - Bad PSU

it looks to me likke 24 and 12 if I am reading it right.

Probably not. That appears to be the output of the main section of the supply, you need the standby section.

PlainBill

[nuklear]

Re: Philips LCD 42PFL5432D/37 - Bad PSU

it looks to me likke 24 and 12 if I am reading it right.

[thelmores]

Re: Philips LCD 42PFL5432D/37 - Bad PSU

And ALWAYS make sure you get 105c (or higher) rated caps......

Some manufacturers will try to get away with 85c caps, and they will not last nearly as long as a good 105c rated caps.

105c caps are also rated for lifetime, whether it be 1000hrs, 2000hrs, 3000hrs, etc.
You want to choose the best caps you can, while at the same time keeping the price reasonable.

[momaka]

Re: Philips LCD 42PFL5432D/37 - Bad PSU

and this is what i seen in the "spare parts list" IC907 9965 000 43345 TEA1507P/N1.

Perfect! I got IC907 down as TEA1507P (this is the PWM controller for the standby circuit).

Now the only thing I couldn't read from the schematic is the output voltages. It looks like it says 21 volts for the top and 12 volts for the bottom one - these voltage are all the way on the right on the schematic. Please verify that the values I read are correct.

So, it looks like the external standby PSU mod will work. Just need to get the value of the standby voltage, remove a few jumpers, wire the external PSU, and it will be good to go.

As for trying to fix the PSU by reusing a transformer from another PSU, it probably won't be possible, unfortunately. The old transformer has 2 auxiliary windings while most computer PSUs only have 1. Save the old transformer in your junk box, though, just in case you run into another transformer with a similar core.

[nuklear]

Re: Philips LCD 42PFL5432D/37 - Bad PSU

I hope I did that right lol. and this is what i seen in the "spare parts list" IC907 9965 000 43345 TEA1507P/N1. Again thanks for helping!

[momaka]

Re: Philips LCD 42PFL5432D/37 - Bad PSU

Yeah, it looks like it should be do-able, since there's only a single output for the standby power.
Does the service manual have a schematic of the power supply? If so, this would be very helpful. We need to determine what output voltage is needed for the standby power. If you know how to read schematics, look up the voltages on the connector next to that 16v, 2200uF Rubycon PX capacitor.
Otherwise you can also post the service manual here or just take a screenshot (with Print Screen key) of the power supply schematic and upload that.
Lastly, can you tell me the part number of IC907? Thanks.

*EDIT*
Actually, just post a screenshot of the schematic if possible. I just saw something that needs to looked at in more detail.

[nuklear]

Re: Philips LCD 42PFL5432D/37 - Bad PSU

Sorry about the pics, Thanks for the links! I am willing to try anything so here is more pics (hopefully done right this time). I want to fix this for my son as a "gaming tv" so it doesnt have to look too pretty but safe I also have the service manual if that would help.

[momaka]

Re: Philips LCD 42PFL5432D/37 - Bad PSU

I stand corrected.

As do I. My appologies for wrongly accusing your friend.

Yep, looks like it's time for a new power supply.

...Or is it?
I've always been a bit optimistic about fixing things, even if they have to be cobbled and kludged together in an ugly way sometimes.
Looking at this power supply, I'm pretty sure we can either wire it to an external power supply or reuse a transformer from another power supply to make it work again.
If you want to try any of that, post an overhead picture of the back (solder side) of the power supply so that I can see what kind of transformer and/or voltages this thing might need and how they can be wired.

[retiredcaps]

Re: Philips LCD 42PFL5432D/37 - Bad PSU

Well here are the pics.

For the 10 inline pics hosted offsite, please read the following

https://www.badcaps.net/forum/showpo...5&postcount=12

for future posts.

[Scenic]

Re: Philips LCD 42PFL5432D/37 - Bad PSU

http://www.shopjimmy.com/philips-996500044559.htm

out of stock though

found this..
http://cgi.ebay.com/250742845392