Philips 42pfl5332 no picture

[CroTech]

Hi there, I have a philips 42pfl5332/10 which was at first hard to turn on, it took some time to turn it on (I know that sounds a lil bit dirty ) joke aside, a few days ago it would not turn on at all...

I knew the problem was with the capacitors on the power board but I was too lazy to replace them before this happened. Finally I have replaced them and now the TV turns on instantly, at least the LEDs but there is only sound and no picture.

What could be the problem?

I checked the fuses on the power board and none have been blown, I checked the voltage regulator and it is fine (3,29V on the middle pin)... I also checked the transformer, although I am not sure if that´s the way to check it.

The pictures will give better description than me blabing...

[tom66]

Re: Philips 42pfl5332 no picture

Make sure the pink insulated connectors going to the power supply are well connected and seated properly. Check if the backlight lights correctly by observing the LCD in a dark room.

[CroTech]

Re: Philips 42pfl5332 no picture

I rechecked them several times, I thought it has to be the problem but no luck...
Also I thought of backlight, could it be that the picture is there but there is no brightness, still no luck, there is definently no picture.

[tom66]

Re: Philips 42pfl5332 no picture

You need to see in a dark room if the screen is lit or not because that is very important in determining where the fault is.

[CroTech]

Re: Philips 42pfl5332 no picture

I will do that, but in a few days, since I am at a dorm and my TV is at home...

Can anyone verify if I checked the transformer secondaries right?
Picture #3 is transformer´s upper side, and picture #7 is the solder side
where I measured the impendance.

[tom66]

Re: Philips 42pfl5332 no picture

That would appear correct; however, the resistance check on single-transformer inverters is generally unimportant, apart from the windings not being open (high resistance.)

[CroTech]

Re: Philips 42pfl5332 no picture

Ok, I have the power board with me and a multimeter...
Is there anything else I could check?

[tom66]

Re: Philips 42pfl5332 no picture

Not really until we know what the fault is, no backlight or no video with lit up screen, diagnosis is completely different.

[CroTech]

Re: Philips 42pfl5332 no picture

I put the power board back on and connected all the cables, turned TV on, it was almost midnight and the sound was on but absolutely no picture, no backlight no picture.

Then I took down the logic board, noticed a little bulge on the 470uf 16V SMD capacitor, replaced it with gluxon 470uF 25V put the logic board back on tried turning it ON for several times and nothing, then all of a sudden TV worked just fine.

Now, I have the problem that when I turn it off I have to keep pushing power button on remote for like 20-30times and then I get the TV working again.

What could cause that problem?

[tom66]

Re: Philips 42pfl5332 no picture

During the fault, check BLON. If BLON is missing (<1V), then the fault is with the main board. If BLON is present (>2V) then the fault is with the inverter/PSU.

[CroTech]

Re: Philips 42pfl5332 no picture

Since I dont have the boards with me, I presume the BLON is the voltage found on two connectors that connect the logic board and power board together?

So u are saying by measuring this voltage while the boards are connected and powered on we can now where to look for the problem?

[tom66]

Re: Philips 42pfl5332 no picture

Yes.

[vbuble]

Re: Philips 42pfl5332 no picture

Hi Lule

I realised you are kind of expert and I will ask you to help me.
I have an Philips LCD TV - 42PFL9732D/10 for about four years.
I did experience several switch-on problems, no picture - sound ok.
After switching off and on again it appear to operate everything in best order.
Few days ago I did not receive any picture at all after many switch on & off.
At the same time sound, remote control and ambilight are fully operational.
Asking your advice.

Vinko - Trogir

[CroTech]

Re: Philips 42pfl5332 no picture

Hi Vinko,

The same thing happens with my TV. Sometimes it takes 30-50 power on and offs to get it working. So I assume we have the same problem. Once I realize and locate the problem I will post the solution here.

Jel sunčano u Trogiru? Oće bit šta za prvi maj