Philips 58pfl4609/f7 TV not working

[drabina]

I have Philips TV model # 58pfl4609/f7. I got it for free (not working of course) and I am trying to trouble shoot the issue. The TV has three boards and if with your help, I could diagnose which board is faulty, I would most likely replace the whole board. So far, the symptoms are:

1. No power at all, no standby light, no flashing lights, backlight doesn't turn on.
2. Standby voltage on the power supply is at exactly 5V
3. No other pins (12,24V) show any voltage
4. Pressing Power button does nothing

Could somebody help me out figure out which board is shot by providing info on what to check next?

[aaronwt6]

Re: Philips 58pfl4609/f7 TV not working

Without any further testing, this would point to the main board. I can't read the pins on the connector going from the power supply to the main board but it would be smart to check the PS-ON pin as the power button is pressed. If you have no or little voltage on that pin, then the main board is almost certainly the culprit. Make sure if you order one that you get an exact match. Usually there is an identifier on the white sticker that shows the board version. Don't order by the model number alone as there may be multiple types.

[drabina]

Re: Philips 58pfl4609/f7 TV not working

Thanks for replying.

I have the following pins on the PS board:

Smaller connector:
175V
175V
NC
GND
NC
SP
NC
ADJ
ENA

Bigger connector:
12V
12V
GND
GND
12V
5V
GND
5V SB
GND
STB
GND
ADJ
ENA

I do not have PS-ON pin or I do not know where to find it.

[freakaftr8]

Re: Philips 58pfl4609/f7 TV not working

I believe ENA is ps_on. Sounds like mainboard as well.

I believe ENA,short for enable.. and that 175 v on small connector, that should be 17.5v

[drabina]

Re: Philips 58pfl4609/f7 TV not working

There is no voltage change on the ENA pin on the bigger connector. I just forgot to check the voltage on the smaller connector (ENA pin) on the PS. Will do that later today when I get back from work.

[drabina]

Re: Philips 58pfl4609/f7 TV not working

Still need help guys. I have purchased a replacement main board but that didn't fix the problem when installed. Same symptoms (5V on standby, no other voltages present, no lights on the TV). When I unplug the TV, wait a bit and press Power button while connecting the power cable, I get 4 green light blinks. Any ideas?

[drabina]

Re: Philips 58pfl4609/f7 TV not working

Anybody?

[freakaftr8]

Re: Philips 58pfl4609/f7 TV not working

You say their standby voltage you have a SB5V and an STB pin. Test each pin in its current state and post the findings.

Also what's the voltage at the primary capacitors on hot side of power supply when in standby?

[drabina]

Re: Philips 58pfl4609/f7 TV not working

Sorry for a delay in responding. Here are the measurements:

SB5V - 5V
STB - 0V (no reading)
Capacitors - 168V (those are the big long capacitors on the PS board)

[freakaftr8]

Re: Philips 58pfl4609/f7 TV not working

Nothing on the 17.5v when you press power button?

[dskall]

Re: Philips 58pfl4609/f7 TV not working

I think STB is your ps_on

[R_J]

Re: Philips 58pfl4609/f7 TV not working

Have you checked the small round (red) fuses F2,F3, on the power supply board, I see shopjimmy has a repair kit for this board, maybe check the fuse resistors like R48 & R15, they should read very low and not open.
Yes it looks like STB is power supply on

[thoma]

Re: Philips 58pfl4609/f7 TV not working

https://www.amazon.com/Philips-UPBPS.../dp/B0772T8WYH

https://www.shopjimmy.com/philips-58...repair-kit.htm

[drabina]

Re: Philips 58pfl4609/f7 TV not working

Nothing on the 17.5V when I press the power button. The round red fuses read 0.1 Ohm on all three of them (F1, F2, F3). R48 and R15 resistors look good too. Could it be the power board? The replacement main board was pulled from a working TV with broken screen so unless it got damaged during shipping, it should be working. I have also noticed that some of the wires go from the main board to the power board thru the LED board. Anything to check on that board?

[freakaftr8]

Re: Philips 58pfl4609/f7 TV not working

I dont have specs on this power supply but if mainboard was not the issue, there's a possibility that mainboard is trying to bend the turn on command bit the power supply has a problem with turning on.

While pressing the power button no you get any voltage change at STB?

[drabina]

Re: Philips 58pfl4609/f7 TV not working

No change at any of the PINs on the power supply board. I have even checked with the remote to make sure button is not the issue.

[freakaftr8]

Re: Philips 58pfl4609/f7 TV not working

Are you getting any voltage the input and power buttons via the small flat white ribbon cable?

Also monitor your 5v standby when you press power button.

[R_J]

Re: Philips 58pfl4609/f7 TV not working

remove cn3 going to the main board, then jump +5vsb to stb, that should turn on the power supply if its working, it looks like it has a series resitor (R71) so no external resistor is needed
R77 goes from that line (after r71) to ground holding Q8 base low in standby condition

[sirentech]

Re: Philips 58pfl4609/f7 TV not working

Hi, I am new here but have been a viewer for quite sometime. Thanks for having this multitopic forum. I also have the Phillips 58PFL4609 flat screen.
It does have a power supply issue. Here is what I can inform you, and I am hoping someone knows where I can find a schematic. Manualsunlimited does not have this one. Anyway, ShopJimmy does carry the repair kit for this for COMMON problems only. I have also read that the kit does not resolve all the issues with regard to no-start and maybe no standby. On the underneath of my board I have 2 smd zeners and 1 or 2 smd transistors that are shorted. On the top side one of the MOSFETS are shorted as well. I am hoping someone has a diagram so I can identify what the zeners breakdown voltages are. I have no problem sharing what I have found out with regard to bad components. Also, it is quite disappointing to look around the iNet and see the excruciatingly painful prices for that PSU. I was very interested in the business that advertises they will upgrade the board to non-inferior parts. Anyway, thanks for any help one may provide.

[tzap]

Re: Philips 58pfl4609/f7 TV not working

Old thread, but bumping it because I have the same problem.

Symptoms were: No signs of life at all. Power button did nothing. Remote did nothing.

Replaced PSU board: No improvement.

Replaced main board: WORKED AGAIN. For a couple of weeks. Then failed again. Same symptoms.

Is it possible something in my TV is killing the main boards? Or do the main boards have a common failure mode and I just hit it twice?