I think i killed it Toshiba 40L1333DB

[alerton]

Re: I think i killed it Toshiba 40L1333DB

something is not right. You are measuring 390V on the caps, that means the PSU is full on and the PFC is running. So that again means either you had forced the PSU on, or the main board is stuck in on mode right now, since it doesn't respond anymore and yet turns on the PSU?

im open to advice and to be honest i was only guessing that it was the psu that went faulty but it could also be the main board i really dont know all i do know is it did work in the morning (apart from the backlights) and then at some point during the process of fixing the backlights the thing stopped turning on at all, no front panel lcd nothing.

[alerton]

Re: I think i killed it Toshiba 40L1333DB

can you upload a picture of the back of the tv showing how all of the boards are connected up

Will do, as it stands right now i have left the leds disconnected from the psu in case that was causing the problem and the main board has the buttons and speakers disconnected as they are still attached to the back panel and the wires donr really reach to have them connected.

[nomoresonys]

Re: I think i killed it Toshiba 40L1333DB

something is not right. You are measuring 390V on the caps, that means the PSU is full on and the PFC is running. So that again means either you had forced the PSU on, or the main board is stuck in on mode right now, since it doesn't respond anymore and yet turns on the PSU?

Could be, then need to check if ps-on voltage changes when going from standby which is plugged in but turned off to power on.

[alerton]

Re: I think i killed it Toshiba 40L1333DB

Could be, then need to check if ps-on voltage changes when going from standby which is plugged in but turned off to power on.

was that comment for me or CapLeaker? as i dont follow what you mean sorry, you need to remember im a idiot and its late here too (thats my excuse anyway ) in fact its only 30 minutes to midnight here so id like to blame alcohol too but saddly i cant drink at the moment as it dont agree with some chemo im having but anyway... happy new year everyone and thanks for all of your help and advice so far.

[vinceroger69]

Re: I think i killed it Toshiba 40L1333DB

schematic for psu may match your board

[nomoresonys]

Re: I think i killed it Toshiba 40L1333DB

It's a test to see if the ps-on signal is working correctly, your board appears to be a vestel with no clear markings on the board as to which pin does what, which some boards have a map of expected voltages and pin numbers. Maybe one of the vestel pros can assist, hope all goes well and you get back to pub crawl shape very soon.

[alerton]

Re: I think i killed it Toshiba 40L1333DB

It's a test to see if the ps-on signal is working correctly, your board appears to be a vestel with no clear markings on the board as to which pin does what, which some boards have a map of expected voltages and pin numbers. Maybe one of the vestel pros can assist, hope all goes well and you get back to pub crawl shape very soon.

trust me you're all vestel pros compared to me, up until 3 days ago i would have said vestel sounded like an updated version of a popular 70's ready meal that i used to think was quite exotic at the time. thanks for your help and kind words.

[CapLeaker]

Re: I think i killed it Toshiba 40L1333DB

if the main board turns on the PSU by itself, there has to be something wrong with it, or some voltage is jumped to PSon. I've still got a few hrs to go

[alerton]

Re: I think i killed it Toshiba 40L1333DB

just for the hell of it i just disconnected the main board from the psu and powered the psu up, still reading 390v on both the main caps if that makes any sense or helps anyone work out whats wrong.

[nomoresonys]

Re: I think i killed it Toshiba 40L1333DB

Wonder if this is one of those always on power supply boards.

[alerton]

Re: I think i killed it Toshiba 40L1333DB

Wonder if this is one of those always on power supply boards.

dont ask me, until 3 days ago i still suspected that there were real live miniature people inside the back of the tv making all the tv shows

[CapLeaker]

Re: I think i killed it Toshiba 40L1333DB

just for the hell of it i just disconnected the main board from the psu and powered the psu up, still reading 390v on both the main caps if that makes any sense or helps anyone work out whats wrong.

Not possible. 240VAC x 1.414 = 339.36VDC. I really doubt it that you have ~280VAC out of the mains plug. So I suggest to check the batteries in your meter.

[alerton]

Re: I think i killed it Toshiba 40L1333DB

Not possible. 240VAC x 1.414 = 339.36VDC. I really doubt it that you have ~280VAC out of the mains plug. So I suggest to check the batteries in your meter.

very strange then, i know its a cheap meter but i also know the battery is good (new 2 weeks ago), im getting 240v at the mains into the board and just double checked and its 390v at both main caps with the main board disconnected or connected , also checked that it was reading 0v at the main caps before powering the board up.

[CapLeaker]

Re: I think i killed it Toshiba 40L1333DB

Dunno... what else to tell you than trying a different meter. 240VAC rectified is 339.36VDC. That means the PFC isn't running. If the PFC runs, it should have close to 400V on the main filter capacitor. The PFC only runs if it gets told to and also means the PSU is on all voltage rails.

[alerton]

Re: I think i killed it Toshiba 40L1333DB

Dunno... what else to tell you than trying a different meter. 240VAC rectified is 339.36VDC. That means the PFC isn't running. If the PFC runs, it should have close to 400V on the main filter capacitor. The PFC only runs if it gets told to and also means the PSU is on all voltage rails.

its a mystery then, previously sordids999 had posted that i should be getting 390v at the main caps and thats exactly what i am getting with the main board connected or not.

[CapLeaker]

Re: I think i killed it Toshiba 40L1333DB

if the PSU is full on and the PFC is running, then yes. But for that to happen either you need to force the PSU on, or there is a BLon signal from the main board to the PSU. Other than that, the PSU is off and the only thing on is the STBY voltage.

[alerton]

Re: I think i killed it Toshiba 40L1333DB

if the PSU is full on and the PFC is running, then yes. But for that to happen either you need to force the PSU on, or there is a BLon signal from the main board to the PSU. Other than that, the PSU is off and the only thing on is the STBY voltage.

Not easy to do 1 handed but I hope these pics show the main board disconnected and 390v at the main caps, also I checked the led connection and there is 78v on that with the main board disconnected too. I hope this helps you reassure me that I haven't lost the plot totally �� and i wouldnt know how to force the power supply on, so i didnt do that i promise.

[sordids999]

Re: I think i killed it Toshiba 40L1333DB

What voltage do you have going to the backlights ?
Measure across the led legend black probe on chassis red probe on red cable and black cable on the psu
Connect everything back together

[alerton]

Re: I think i killed it Toshiba 40L1333DB

What voltage do you have going to the backlights ?
Measure across the led legend black probe on chassis red probe on red cable and black cable on the psu
Connect everything back together

measuring chassis to red with main board connected = 121v (same with main board disconnected)

[sordids999]

Re: I think i killed it Toshiba 40L1333DB

Can u test this again with the legend disconnected please what's the voltage (everything connected again apart from the led connector )
Did you test the leds before reassembling?
I always thought 121v from the psu is either still an open led or a faulty power supply ?