Philips 55PUS6262/12 always ON but no picture

[tandkramstub]

Hello!
So I was given a broken LED-TV with some unusual issues.
When I plug it in, it turns on and stays on, and does not respond at all.
The red standby light never comes on, it just switches on the backlight LED's and just stays that way.

The mainboard has a couple of green LED's that comes on and stays on, and I can't visually see any swollen or burnt components anywhere.

I replaced the T-con board to no awail and now I have started measuring voltages, but electronics on this level is above my knowledge.

The only clue I have is when I measure the voltages on the connector for the mainboard on the PSU-board, I am missing the 3,5V on both of the lower pins in the black connector in the pic below. I've tried applying 3,3V via an external power supply, but no change.

Any ideas?

[trunks81]

Re: Philips 55PUS6262/12 always ON but no picture

What is the chasis number of this type ?

[yokoono]

Re: Philips 55PUS6262/12 always ON but no picture

Pin for activating p.s. is ps_on. Put there + 5v (max.).

[tandkramstub]

Re: Philips 55PUS6262/12 always ON but no picture

What is the chasis number of this type ?

Hm I have a serial number if that helps?

[dick_barton]

Re: Philips 55PUS6262/12 always ON but no picture

A good starting point is to give the voltage readings of the two connectors. Remember there are two rows of pins. Give the connector name then the pin number, pin name, voltage read.
Some pictures of your boards would also be useful.

[trunks81]

Re: Philips 55PUS6262/12 always ON but no picture

Hm I have a serial number if that helps?

there is an bigger sticker on the tv with also the type and chasis number so i can look up the service manual for u

[tandkramstub]

Re: Philips 55PUS6262/12 always ON but no picture

Right, I've finally been able to measure a bit more and taken some pictures as well.
I've focused on the black connector on the PS board which goes directly to the main board.
The results are like this:
Left row:
On/Off: 3,25V
NC: 2,95V
GND: has contact with chassis
GND: has contact with chassis
+12V_A: 12,0V
+12V: 12,0V
+12V: 12,0V
+3,5V: 0V

Right row:
DIM: 2,4V
PS_ON: 3,0V
GND: has contact with chassis
GND: has contact with chassis
+12V_A: 12,0V
+12V: 12,0V
+12V: 12,0V
+3,5V: 0V

[tandkramstub]

Re: Philips 55PUS6262/12 always ON but no picture

there is an bigger sticker on the tv with also the type and chasis number so i can look up the service manual for u

These are the ones I've found, hope it helps

[trunks81]

Re: Philips 55PUS6262/12 always ON but no picture

its a TPM17.7E LA

[dick_barton]

Re: Philips 55PUS6262/12 always ON but no picture

Can you post a photo of the underside of the power supply. Basically the reverse of the picture in your first post. Just want to check that the 3.5V is actually wired up on this board.

[tandkramstub]

Re: Philips 55PUS6262/12 always ON but no picture

Can you post a photo of the underside of the power supply. Basically the reverse of the picture in your first post. Just want to check that the 3.5V is actually wired up on this board.

No problem, here's a picture of the whole PS and a close-up of the back of the terminal, the 3,5V is on the two pins just above the text "CN9101".

[tandkramstub]

Re: Philips 55PUS6262/12 always ON but no picture

I don't know if it helps, but when the TV is on, two green LED's on the main board comes on and stays on the whole time. I don't know if they should, if they should blink or if there should be more of them.

[dick_barton]

Re: Philips 55PUS6262/12 always ON but no picture

The 3.5V is connected to jumper J9834 but I cannot see where it goes from there since the picture is not large enough. It does look as though it may not be connected since there appears to be many components not mounted on the board very close by to it.
Can you trace where J9834 goes?

[tandkramstub]

Re: Philips 55PUS6262/12 always ON but no picture

The 3.5V is connected to jumper J9834 but I cannot see where it goes from there since the picture is not large enough. It does look as though it may not be connected since there appears to be many components not mounted on the board very close by to it.
Can you trace where J9834 goes?

I've tried to take some better pictures now...

[dick_barton]

Re: Philips 55PUS6262/12 always ON but no picture

It looks as though the 3.5v is not connected on this board.

[R_J]

Re: Philips 55PUS6262/12 always ON but no picture

The 3.5v is supplied via L9303 (which is not populated) I suspect U9301 is also missing (12v to 3.5v reg.)

[tandkramstub]

Re: Philips 55PUS6262/12 always ON but no picture

Alright, that explains why I am missing the 3,5V, but then I don't have aclue to why the TV doesn't work.
Or does it mean that the power supply is likely ok and that the main board is the culprit here?

[dick_barton]

Re: Philips 55PUS6262/12 always ON but no picture

It is looking like a problem on the mainboard. If you disconnect the wifi module will it power up as normal?

[tandkramstub]

Re: Philips 55PUS6262/12 always ON but no picture

It is looking like a problem on the mainboard. If you disconnect the wifi module will it power up as normal?

No change at all.

[tandkramstub]

Re: Philips 55PUS6262/12 always ON but no picture

Anyone have a clue to how to start troubleshooting the main board then? Is it "usually" a simple component that gives up, or is it more likely that it's a chip or something that you can't really check as a novice?