Phillips 32PFL3504D/F7 LCD

[Mad_Professor]

I got a Phillips 32" in for repair today.

Phillips 32PFL3504D/F7

The tv turns on, shows the pretty "Phillips" logo then goes dead completely including the power light on the bottom. But you can restart it. I think the inverter is ok since the screen was alot brighter then my 42".

I open it up.

This board plagued with Su'scon and Jamicon caps all over.

Jamicon
1x 16v 3300 uf SK 25x12.5x5
1x 6.3v 2200 uf SK 20x10x5
1x 35v 1000 uf SK 20x12.5x5
2x 25v 1000 uf SK 20x10x2.5
2x 6.3v 1000 uf SK 16x10x3.5
1x 25v 470 uf SK 12.5x10x3.5
1x 50v 220 uf SK 12.5x10x3.5
1x 25v 220 uf SK 12.5x8x2.5 pinched for 3.5 hole
1x 25v 100 uf SK 10x6.5x 2.5 pinched to 3.5 hole

small ones

2x 10v 220 uf SK 5x12.5x2.5
3x 50v 22uf SK 5x12.5x2.5
5x 50v 10uf SK 5x12.5x2.5
1x 50v 3.3 uf SK 5x12.5x2.5
2x 50v 2.2uf SK 5x12.5x2.5


Su'scon
1x 10v 2200 uf SL 20x10x5
3x 16v 100 uf SL 12x6x2.5
1x 10v 100uf SL 5x12.5x2.5
1x 25v 47 uf SL 5x12.5x2.5
4x 50v 1 uf SL 5x12.5x2.5

The problem is there are so many small ones and only few big ones.

I don't have an ESR or capacitance tester so... I should probably invest in one soon.

Anyways?
Should I replace all of them?

[tom66]

Re: Phillips 32PFL3504D/F7 LCD

This is one of those Philips "creations" that mixes both power supply and inputs on one board. Ugh!

Anyway, the first logical step would be to check for a supply voltage coming out of that power supply.

[Mad_Professor]

Re: Phillips 32PFL3504D/F7 LCD

Spent $25 on caps and Recapped board. Still have same issue. Unplugged inverter, t.v set stays on.

Tested all 5 CCFL transformers read 560 ohms across coils.

Not sure how to test the lamps. I have some CCFL bulbs from a dead 22" viewsonic monitor.

[Mad_Professor]

Re: Phillips 32PFL3504D/F7 LCD

Pictures of inverter board...
Two shots, so if you can't see it try the other one.

Also I hear a squelching sound coming around T1950 when being discharged *IE unplugged.* I have not tested this one.


Any help is appreciated.

[tom66]

Re: Phillips 32PFL3504D/F7 LCD

I recall a similar fault like this was caused by a shorted MOSFET on the power board, for the inverter. You could try this trick to locate the failed device:

http://www.youtube.com/watch?v=XhqwC...el_video_title

[Mad_Professor]

Re: Phillips 32PFL3504D/F7 LCD

I wouldn't even know where to begin, I need some guidance on this.

[tom66]

Re: Phillips 32PFL3504D/F7 LCD

I wouldn't even know where to begin, I need some guidance on this.

Try the trick in the video. You can use the freeze spray to find which transistors are shorted.

[Mad_Professor]

Re: Phillips 32PFL3504D/F7 LCD

Try the trick in the video. You can use the freeze spray to find which transistors are shorted.

Since freeze spray is 25 bucks a pop. Would a upside-down can of "compressed air" work? since it uses the same refrigerant used in freeze spray.

[tom66]

Re: Phillips 32PFL3504D/F7 LCD

Since freeze spray is 25 bucks a pop. Would a upside-down can of "compressed air" work? since it uses the same refrigerant used in freeze spray.

I can't see why not.

[Mad_Professor]

Re: Phillips 32PFL3504D/F7 LCD

So I work up the nerve to do the freeze spray and did it several times, but no components transistors are heating up fast enough to make a difference.

I didn't do the big ones attached to heatsinks though.

I'm hearing a squelch in the area circled red when the set is unplugged. I used the paper tube trick to narrow it down but I can't determine the point of origin.

Also I was thinking maybe that large cap circled in green on the inverter is bad. It's a HEC 270 uF 200 WV <--- whatever that means, 85*C.
Other markings NEG, LS, C/X22.

Any other ideas?

[budm]

Re: Phillips 32PFL3504D/F7 LCD

The MOSFET's for the inverter transformers are on the heatsinks to the right of the pictures. Did you check all 4 of those MOSFET's on the heat sink?
What is the chassis number of this TV?

[budm]

Re: Phillips 32PFL3504D/F7 LCD

Bythe way, I myself just picked up a set of six air dusters from Costco on sale for $15, I have been using them for troubleshooting for years.

[Mad_Professor]

Re: Phillips 32PFL3504D/F7 LCD

The MOSFET's for the inverter transformers are on the heatsinks to the right of the pictures. Did you check all 4 of those MOSFET's on the heat sink?
What is the chassis number of this TV?

chassis number? you mean the model? 32PFL3504D/F7

I went ahead and spray the 4 fets on the heatsinks, but it had no effect and/or did not heat up.

I'm so close, I just need to find the faulty component.

[budm]

Re: Phillips 32PFL3504D/F7 LCD

On the back of the TV where they put the model number, there will be "Chassis xxx.xxx.xxx" on that same tag. See picture, then you will go to www.elektrotanya.com using that chassis number to get the service manuals if they have them.

[tom66]

Re: Phillips 32PFL3504D/F7 LCD

On the inverter board what voltage do you get across the big Panasonic caps you have replaced?

The squelch probably comes from the yellow transformer. Since it's a cheap-o self-resonant two transistor converter anything could happen when the supply voltage drops out.

[Mad_Professor]

Re: Phillips 32PFL3504D/F7 LCD

So I've been ill for a few days. But now I'm back.

On the back of the TV where they put the model number, there will be "Chassis xxx.xxx.xxx" on that same tag. See picture, then you will go to www.elektrotanya.com using that chassis number to get the service manuals if they have them.

There doesn't appear to be one. Picture below.

On the inverter board what voltage do you get across the big Panasonic caps you have replaced?

The squelch probably comes from the yellow transformer. Since it's a cheap-o self-resonant two transistor converter anything could happen when the supply voltage drops out.

The inverter board, not sure which one you're talking about. The big one on upper left is hec. The one to the right behind the heatsink used to be a Jamicon SK 470uF 100V cap and I replaced it with a Nichicon PW cap.

Getting a voltage will be difficult, since I need to disconnect the CCFL connectors and prop the board up and put the probes on the cap, anything can happen.

[tom66]

Re: Phillips 32PFL3504D/F7 LCD

The two dark blue and gold caps with the "T" shaped vent are Panasonic capacitors.

[Mad_Professor]

Re: Phillips 32PFL3504D/F7 LCD

The two dark blue and gold caps with the "T" shaped vent are Panasonic capacitors.

Those are indeed pannys 220uF 100V FC caps they replaced su'scon SL.

[Mad_Professor]

Re: Phillips 32PFL3504D/F7 LCD

bump.

[tom66]

Re: Phillips 32PFL3504D/F7 LCD

100V? That's quite high... what is the voltage across them?