Philips 40PFL3008T stopped working

[Acerman123]

My 40" Philips 40PFL3008T TV turned off while in use, before that there were no signs of issues. The TV turned off, no smoke, no sound of anything burning and no bad smell, it just turned off and haven't powered on since.

Caps on power board look good externally. I have never performed any kind of troubleshooting of TVs but I still wanted to try finding possible failed part. I read that the power board is suppose to have 5V standby voltage on one pin of the connector which connects to the mainboard. I measure connector labeled CN4 on power board, board is Vestel 17IPS20P.

I get several voltages around 16V but no 5V. As far as I know there should only be 5V voltage and nothing more so something is definetely wrong with the power board?

Also, if the board is faulty, I see that there are Vestel 17IPS20 boards for sale, without the letter P at the end, one seller lists this exact TV model to be compatible, but is it really, does the P have any other meaning than Philips maybe, original part? Also, in case there are regional difference in boards regarding voltage, I do live in Europe.

[ReeceyBurger123]

Re: Philips 40PFL3008T stopped working

You will only get 5v if the Mb turns it on, unplug the motherboard and check what voltage you have on either side of the secondary diodes on the Psu. Also what does the set do stuck in standby ?

[Acerman123]

Re: Philips 40PFL3008T stopped working

The TV does not react to power cord, the standby led does not turn on.

[ReeceyBurger123]

Re: Philips 40PFL3008T stopped working

Ok what voltage do you have on the cathode side of the diodes on the Psu ?

[Acerman123]

Re: Philips 40PFL3008T stopped working

OK, first I must apologize and say that I don't have the best knowledge on these, I have replaced some capacitors on PC motherboards and done some mods by following detailed instructions, my knowledge on basics could be much better.

However, I unplugged the power cord and put the multimeter on diode test mode. With most diodes there are values like around 400 and they settle to spesific number and stay there when I keep prongs in place. With three diodes there is constant beep and the value drops to zero. I did not desolder them and as I was doing some Googling that might produce false results. However, three of those four bigger ones produce different results.

[ReeceyBurger123]

Re: Philips 40PFL3008T stopped working

Ok, what I meant is can you unplug the motherboard connector that goes to the Psu. Then there are some diodes standing up near the connector. Put the black meter probe on chassis ground then the red on the side of the diode that has a stripe near the motherboard connector. Plug the Tv into mains and set the meter to 20v Dc.

What voltage do you get after doing this ?

[Acerman123]

Re: Philips 40PFL3008T stopped working

OK, so with the black one connected to chassis and red touching the striped end of diodes I only get results on one which shows 0,4V, it is the first from right (picture attached). That same also didn't produce constant beep when I tested with diode testing mode.

[ReeceyBurger123]

Re: Philips 40PFL3008T stopped working

Ok then the Psu is faulty, you should always have 12v on one end of them diodes with the Psu connected to mains power. You can either replace the Psu or I could help assist you in repairing it but it might not be easy, let me know what you want to do

[Acerman123]

Re: Philips 40PFL3008T stopped working

OK, I really don't know how difficult task it's going to be if I try to repair

I attached better picture just in case to show the board better, the pic shows power connectors and those diodes I measured.

I did find this page where they sell board which if I understood correctly they say is compatible:

http://parts-tv.com/en/Philips-INVER...)-996590006643

But is it? Does the letter P in the PSU model number just mean that it is original Philips part?

[ReeceyBurger123]

Re: Philips 40PFL3008T stopped working

The P doesn't matter as long as the connectors are the same size physically also that the Psu is for the 40" size Tv which the linked one is so it will work

[Acerman123]

Re: Philips 40PFL3008T stopped working

OK, I might try getting one, however that company charges 41€ for shipping which brings the total cost bit too high.

I do have sharp soldering iron (Atten something) and if it is possible to find reliable parts from eBay I guess I could also try to repair, but with limited actual knowledge, I don't know what will happen

[ReeceyBurger123]

Re: Philips 40PFL3008T stopped working

The fault will likely be in the primary switching section of the psu and will need a fair bit of smd as well as through hole work. Firstly have you checked what voltage your getting across the main Dc filter caps ? Put the meter to 600v dc then out the black probe on the stripe on the cap and red on the other leg.

[Acerman123]

Re: Philips 40PFL3008T stopped working

Hmm, no I haven't... I'm bit too scared to do measurement when the power cord is plugged in and precision is needed to avoid damage... Also, I'm not exactly sure which capacitors you mean...

It might be better for me to replace the board just to avoid damage.. I found this on eBay:

http://www.ebay.co.uk/itm/291748718085

Connectors look same and it's fron 40" TV?

[ReeceyBurger123]

Re: Philips 40PFL3008T stopped working

Ok it will be easier to replace in your case due to lack of experience it could end up with you getting hurt or blowing something up no offence buddy Also that should work.

[electro_nico]

Re: Philips 40PFL3008T stopped working

Casualmente, estoy reparando un tv del mismo modelo y averia. Voy a sustituir varios componentes, cuando lo haga indicaré el resultado de la reparación

[ReeceyBurger123]

Re: Philips 40PFL3008T stopped working

Casualmente, estoy reparando un tv del mismo modelo y averia. Voy a sustituir varios componentes, cuando lo haga indicaré el resultado de la reparación

I dont speak Spanish neither do most people here, can you translate please ?

[diif]

Re: Philips 40PFL3008T stopped working

Courtesy of Google Translate "Coincidentally, I 'm repairing a TV of the same model and breakdown . I will replace several components , when I do I will indicate the result of repair"

[Acerman123]

Re: Philips 40PFL3008T stopped working

I havent't hurried buying new board since I don't watch that much TV anyways... I do have working CRT TV if I absolutely needed to watch TV much older than my Philips and still working!

I decided to measure those diodes since I felt like I was able to do that. I disconnected them from the board and looks like of those three suspected bad diodes only one is really faulty, D210 if I read correctly. Those two which beep when connected to board will show results when off from board, ranging from 266 to 285. Connected them back to board and beeping returns.

When measuring I first removed D211 completely but as far as I know I can just disconnect the other leg? I did that with the other two, didn't remove them from board.

Edit: I ordered measurement cords (or whatever they are actually called ) which have hook mechanism, I might be condifent enough to measure those caps with those.

[budm]

Re: Philips 40PFL3008T stopped working

The diode may be connected in parallel with low Ohms resistor so you need to trace out how the diode is connected in the circuit.

[Acerman123]

Re: Philips 40PFL3008T stopped working

I have very very limited knowledge about these... but since that one resistor beeps when disconnected to board and no matter which way I put prongs, that one is clearly faulty?