Philips 42PF9431D/37 LED blinks 5x(red)

[tlerohl]

Hello,

This blinking LED would happen off and on for a few yrs. I would unplug the power cord and plug it back in and it would work again for anywhere from a month to 6 months. This last time it wouldn't come back on. I have attached Pics. You will notice a missing CAP in image 4329. I took (2) Samxon 680uf 100v caps out because of a post I read but don't know which brand to replace them with. I tested a cap I bought at Radio shack (for testing purposes only) and got a reading within .11 uf of the rating but when I tested these 2 caps I get something that says 0.F (which I guess means they are bad). Any help would be much needed and appreciated.

[tlerohl]

Re: Philips 42PF9431D/37 LED blinks 5x(red)

Sorry, I thought I added the pictures but here they are.

[Moreno83]

Re: Philips 42PF9431D/37 LED blinks 5x(red)

Could you please heat up the board with a hairdryer? Do it for a few minutes and see if the tv will come on again. If so , you probably have bad capacitors on the powersupply.

[tlerohl]

Re: Philips 42PF9431D/37 LED blinks 5x(red)

Should I reinstall the 2 caps I removed? This would be the only way to know if this works.

[ReeceyBurger123]

Re: Philips 42PF9431D/37 LED blinks 5x(red)

Yes install the caps lol, if they are failed replace them with new low esr ones like Panasonic fr series.

[tlerohl]

Re: Philips 42PF9431D/37 LED blinks 5x(red)

OK, So lets first start with the LED flashed 7 times not 5. I think I read too many forums about 5 blinks before taking things apart and posting.
With that said, once I re-installed the 2 caps initially I got the 7 blinking red lights. Then we put a hair dryer to the board and the tv powered up.

Please tell me what my next step should be. Your help is appreciated!

[tlerohl]

Re: Philips 42PF9431D/37 LED blinks 5x(red)

Bump

[vinceroger69]

Re: Philips 42PF9431D/37 LED blinks 5x(red)

if the tv powered up when heated you need to narrow down the area your heating to find the bad parts but my guess its a bad capacitor with high esr (heat tempory brings it down hence tv works) maybe fully re cap the power supply.

[tlerohl]

Re: Philips 42PF9431D/37 LED blinks 5x(red)

How would I know what Caps to buy for a full recap? I am open to it. (I waited before posting until I had a meter that could read higher capacitance. (Mine only went to 40 farad which is why I couldnt get a reading on the 2 caps I pulled). Bought a nice Fluke. I am ready to try this and appreciate any help provided.

[tlerohl]

Re: Philips 42PF9431D/37 LED blinks 5x(red)

bump

[tlerohl]

Re: Philips 42PF9431D/37 LED blinks 5x(red)

bump

[ReeceyBurger123]

Re: Philips 42PF9431D/37 LED blinks 5x(red)

Need voltage lists. Vs, va, 15v etc.

[tlerohl]

Re: Philips 42PF9431D/37 LED blinks 5x(red)

Of each Cap? I will have to remove each one or at least one of each size to figure that out. There isnt a list based on model of TV or board? I would hate to not get them all back in the right place a week or two later (once I have the replacement caps).

Does this pic help at all?

[tlerohl]

Re: Philips 42PF9431D/37 LED blinks 5x(red)

bump

[vinceroger69]

Re: Philips 42PF9431D/37 LED blinks 5x(red)

basically how i recap a board is remove each capacitor one at a time write down the circuit board location number then take a note of the voltage and uf of the capacitor then you can measure its height/width (some times this does not matter if you have the room on the pcb for larger replacements)
so do this for all the capacitors on your board i usually leave the largest one on the primary side thats usually ok then get a list of the others and order replacements i usually use panasonic fc/fm/fr series if you had a capacitor/esr meter you could of measured each one and only replaced any thats out of spec.

[tlerohl]

Re: Philips 42PF9431D/37 LED blinks 5x(red)

I do. I bought a Fluke 177 so I could read capacitance. Don't I need to remove each one from theboard to get a proper reading?

[vinceroger69]

Re: Philips 42PF9431D/37 LED blinks 5x(red)

that only measures capacitance i think you need to measure esr as heat is making the set work
this is one of the best budget esr meters at the minute and can measure a lot of other components too,
http://www.ebay.com/itm/182321753067
and yes best to remove the capacitor and test you maybe able too narrow down which capacitor is bad as heat is making the psu work maybe get a cardboard tube and aim the air down that so you can narrow down the area which makes the psu work then narrow down the area too the bad capacitor takes time but can be done this way but how i see it all the capacitors are probably the same age so if ones failed the others may be not far of failing
do not heat the capacitors too much as they can explode with too much heat.

[cliff_hootarski]

Re: Philips 42PF9431D/37 LED blinks 5x(red)

Short answer to your question is, YES you do have to remove the caps to test for proper capacitance and ESR.

[Agent24]

Re: Philips 42PF9431D/37 LED blinks 5x(red)

A capacitance meter is not as useful here as an ESR meter, because it's usually the ESR of the capacitor which changes (increases), rather than the capacitance changing.

The (likely) reason your TV works when you heated it with the hairdryer is that the capacitors which have failed are returning to a semi-usable state (their ESR drops) when you heat them. Sometimes capacitors fail with reduced capacitance, but in that case heating them does not usually do anything.

You need to check them all with an ESR meter to find the bad ones, though you should test their capacitance too, just to be thorough. Occasionally a capacitor may fail with reduced capacitance while its ESR reads fine on the meter.

Yes you should do component tests out-of-circuit for the most accurate readings.