Philips 42PFL5432D/37

[budm]

Re: Philips 42PFL5432D/37

What I did on one of the TV I fixed is to leave the T-CON metal cover off, then I use a small CPU cooling fan to blow cool air on to the T-CON board using the switched 12VDC for powering up the fan, another TV I used heatsink to cool the IC.
http://s807.photobucket.com/albums/y...%20LTV-32W3HD/

Do you have a can of compressed air duster? They sell them at Costco 3 cans for about $6, just turn the can upside down and blow the cold air on the T-CON to see if it will start working again, then you can try just cool each IC or components on the T-CON board to find out which one is temperatue sensitive.

[budm]

Re: Philips 42PFL5432D/37

That is a cap, C69 , in the picture that looks bad. You should be able to take a voltage reading on the cap, the bar is the Postive side in this case. You can try cool spray on this cap.

[budm]

Re: Philips 42PFL5432D/37

By the way, your camera should have MACRO mode for closed up function.

[bbjunkie]

Re: Philips 42PFL5432D/37

Careful, some canned air contains liquid propellant and when the can is turned upside down, it comes out instead of air (I found out the hard way spraying "air" at my digital camera sensor) I suggest if you are going to try this, use a can of freezer spray instead.

Do you have a can of compressed air duster? They sell them at Costco 3 cans for about $6, just turn the can upside down and blow the cold air on the T-CON to see if it will start working again, then you can try just cool each IC or components on the T-CON board to find out which one is temperatue sensitive.

[budm]

Re: Philips 42PFL5432D/37

The one from Costco works just fine. I used to buy the expensive freeze spray made for electronics repair. You can try Radio Shack, they used to sell these freeze spray for electronics troubleshooting. You can verify if the canned air is OK or not by just spraying it on to a glass and see if it leaves any residue.

[Lobo]

Re: Philips 42PFL5432D/37

That is a cap, C69 , in the picture that looks bad. You should be able to take a voltage reading on the cap, the bar is the Postive side in this case. You can try cool spray on this cap.

So looking at the pic named "top angle" would you say that the left side is positive?

[Lobo]

Re: Philips 42PFL5432D/37

Uh, I went to check the voltage with my multimeter and the solder holding the component was so hot that it fell right off the board...

The funny thing is after that fell off, my picture came back. The TV works now. I'm baffled, what do I do now? Just leave it and worry about it being a fire hazard? Or what? haha

[budm]

Re: Philips 42PFL5432D/37

So right now the cap is no longer in place? I had a feeling that the cap has high leakage or shorting out, I will not run the TV without it since the circuits may be exposing AC ripple voltage due to missing filter cap, unless there is another cap with the same value hooked up in parallel with this cap.

[Lobo]

Re: Philips 42PFL5432D/37

Yeah, the cap is no longer there. So what do I replace it with? My cheap multimeter was reading about 15-16 V.

[budm]

Re: Philips 42PFL5432D/37

15~22uf25v surface mounted or try using low ESR through hole type. But one thing that bother me is that the voltage is that high, I do not expect it to be higher than 12vdc. I would look for replacement T-CON because I think it will go out completely soon.

[Lobo]

Re: Philips 42PFL5432D/37

Yeah, I was thinking of just replacing it because they are relatively cheap. I found one for 20 dollars.

But anyway, I wonder if PoteauPet has taken another look at her T-conn board? Curious to see if she has the same prob.

[budm]

Re: Philips 42PFL5432D/37

On the surface mounted polarized cap, the BAR is positive, you can verify that with the DMM.

[Abbeyjack]

Re: Philips 42PFL5432D/37

I have hit a wall. I was following this post here, just to quickly sum up my symptons for you......

I was following along nicely, things were good, then i got to the step where it was asked to measure the pins on the voltage regulators on the t-con board. I measured the first one, which would be the one of the top of the pic.



Post #170


Pin 1- 2.48
Pin 2- 0
Pin 3- 3.25

Exactly what the OP got, and was said it was accurate. cool .

Was going to check the second one( the right side of the pic), went i put the red tip of my meter on PIN 2 it caused a little "zap" and very high frequency sound and THE PICTURE CAME ON!! I fiddled with it a couple times and the picture would go on and off as i was poking it. with the zap and high frequency sound.

I sat back and it stayed on. So, i think i found the problem, although i dont know what i found!!

Could this be a bad voltage regulator? Is it just a bad soldering joint? I have never messed with it, so can joints just go bad over time and need to be fixed?

For clairification, while i am measuring the second voltage regulator, i have sound, green power light, back lights on, no picture.

Pin 1- 0
Pin 2- 5.38
Pin 3- 0

Thank you for reading this and I hope it makes sense.

I was able to measure the second voltage regulator while the picture was on and it was different.

Pin 1- 2.5
Pin 2- 3.5
Pin 3- 0

Please help me understand what's going on.

[budm]

Re: Philips 42PFL5432D/37

How about the pictures of your board, so we may see what is going on with YOUR board?

[retiredcaps]

Re: Philips 42PFL5432D/37

For clairification, while i am measuring the second voltage regulator, i have sound, green power light, back lights on, no picture.

Pin 1- 0
Pin 2- 5.38
Pin 3- 0

A part number and picture for the above would help.

[Abbeyjack]

Re: Philips 42PFL5432D/37

I circled the voltage regulator in question in red in the one photo.

Part # 63A3 71Q5Z


Thanks

[tom66]

Re: Philips 42PFL5432D/37

Going by its position I'd say that's a MOSFET not a voltage regulator.

[Abbeyjack]

Re: Philips 42PFL5432D/37

according to post #170 its a voltage regulator. Of course I am only going by what I read on here, I really dont know what either one are! Im learning as I go!

[budm]

Re: Philips 42PFL5432D/37

That looks like MOSFET to me too, it is QP17 and its GATE pin driven by UP2 pin 4, it is part of the switching power supply. Can you read the P/N on UP2?
You can see V5.6V input feeding the pin of the inductor LP4, the other pin is connected to the Drain (Middle/tab) pin of the MOSFET, the output Diode Anode (DP21) is also connected to the Drain pin, the Cathode pin is the output pin, so it looks like a Boost regulator.

[retiredcaps]

Re: Philips 42PFL5432D/37

Part # 63A3 71Q5Z

As tom66 and budm both mentioned now, it is a mosfet.

http://www.datasheetarchive.com/63A3-datasheet.html

When I don't get clear focused pictures, I can only guess at what the part can be.

Many people don't realize how difficult remote troubleshooting is when we don't have the board in front of us. You are the eyes, ears, etc for us.