Vizio E470i no power

[AcGeorgiegirl]

Re: Vizio E470i no power

OK. If you can't find a 500ohm resistor (I could only find 470ohm) then look for a 1Kohm resistor. That will be one with 1st band-BROWN (1), 2nd band-BLACK (0), 3rd band-RED (00). GOLD or SILVER for the 4th band but is not important right now.
On the Power Board jack P701 with the TV plugged in the AC measure Pins10-15 and 20-21 and see if you're getting 5Vdc.

I am wondering if you actually have the schematics for my psb? I can't locate the P701 jack you are referring to, and would be great to have the schematics!!

[newtothis]

Re: Vizio E470i no power

I haven't found anything but maybe someone else will have an idea.

That is a SOT not a Cap

[AcGeorgiegirl]

Re: Vizio E470i no power

OK. If you can't find a 500ohm resistor (I could only find 470ohm) then look for a 1Kohm resistor. That will be one with 1st band-BROWN (1), 2nd band-BLACK (0), 3rd band-RED (00). GOLD or SILVER for the 4th band but is not important right now.
On the Power Board jack P701 with the TV plugged in the AC measure Pins10-15 and 20-21 and see if you're getting 5Vdc.

I don't want to keep bugging folks, so I won't post again, but am still wondering what jack you are suggesting I test? I find no other comm port other than the one I previously tested, that goes to the Main, and one that looks like to belongs to the panel(it has video-related pins, but only 4). Also, were you advising using a 1k ohm resistor only on this P701 jack, or for both it and the connector I blew a cap on(the Main connector)?

[budm]

Re: Vizio E470i no power

I think he meant P201:
https://www.badcaps.net/forum/attach...3&d=1432326777

[AcGeorgiegirl]

Re: Vizio E470i no power

On the pic you linked a closeup of the cn201, which is the jack we've been talking about thus far. Is that what you mean? There are only 12 pins. I can't see a P201 or P701...anything with that larger amount of pins.

[AcGeorgiegirl]

Re: Vizio E470i no power

I am about to go try the same procedure (jumping using a 1k ohm resistor from 5v stndby to the ps-on and bl-on pins) on the original board. I damaged the replacement one, fyi.

[AcGeorgiegirl]

Re: Vizio E470i no power

I first tried it just using a wire(not resistor), and I did get a 5.2 v onto each of the pins(bl-on and ps-on). So what does that mean??? How can it actually switch on the backlight and the power, without being connected to the Main?(yes, I'm still stuck in not understanding this, I guess). How could I get the backlight and power on by jumpering, unless the main is connected?

[newtothis]

Re: Vizio E470i no power

I think he is getting confused with another board maybe.

The PSU send 5v standby to main, The main needs the 5v to operate the circuit that detects you switching it on... When you switch it on the main sends power to the PS_ON pin... The PSU detects the ON signal and switches the rest on.

I have no idea why the SOT blew on the PSU, Unless you shorted the incorrect pins but using a resistor would stop damage usually occurring.

If you get the voltages come up on the other PSU by jumpering the PS_ON then list each pin name and what voltage you have.

Pin 1 - 12v
Pin 2 - 5v

etc

etc

[AcGeorgiegirl]

Re: Vizio E470i no power

I just tried it just using a wire(not resistor) and below are the pin readings. But...the backlight still doesn't come on. ( I realize that I just need to check v for the ps-on, but it can't do anything without the Main). I did leave the ps connected to what I am thinking must be the backlight or panel...the cn301. I'm going to take a pic for you guys and post it of this jack.

pin 1 stndby - 5.21v
pin 2 stndby - 5.21v
pin 3 Gnd
pin 4 Gnd
pin 5 Gnd
pin 6 12v - 11.89v
pin 7 12v - 11.89v
Pin 8 PS on/off - 5.21v
Pin 9 Blu on/off - 5.21v
Pin 10 PWM1 - 5.21v
Pin 11 PWM2 - 5.21v
Pin 12 NC

[AcGeorgiegirl]

Re: Vizio E470i no power

I also tested the CN302 jack pins while the 2 jumpers were still intact on the CN301, using a 200 on the v dial. Here's the results:

Pin 1 LED1 - 60 to 70v
Pin 2 N.C
Pin 3 VOUT1 - 121 to 130v
Pin 4 N.C
Pin 5 LED2 - 61 ti 72v
Pin 6 N.C
Pin 7 VOUT2 - 120 to 128v

[AcGeorgiegirl]

Re: Vizio E470i no power

I also tested the CN302 with the 2 jumpers off. Got a depleting down to nothing reading on all pins that had any voltage before.

[newtothis]

Re: Vizio E470i no power

Main is irrelevant to this now.

You have the voltages all coming up yet still no backlight.

I am sure this is another case of bad LED strings.

Let others pipe in and lets see what they say

[Andrew F. Ali]

Re: Vizio E470i no power

I am so sorry...I mixed up the schematics.....I was looking at a Sharp TV Schematic....Thanks BUDM and newtothis....As for asking many questions, bugging the experts for advice, I think there is no one on this forum who would think this of anyone...I see that you have reached somewhere with the Power board self test...From what I see your Power board is working...and from the reading on CN302...I would tend to agree that you may be suffering from a LED string is 'open circuit' and therefore shutting down the power supply...

[AcGeorgiegirl]

Re: Vizio E470i no power

Thanks for the update, Andrew, no worries! Ok, so the consensus is a LED string so far. I'll go do some research...haven't heard that term yet! I guess it's good news that it's most likely not a Main-board issue. I wasted the money on a replacement Power Supply already. Without the schematics, I'm assuming this'll be a guessing game for me to find where this is located, not to mention how to test it. Any ideas how to get Vizio to supply me with the schematics?

[newtothis]

Re: Vizio E470i no power

Thanks for the update, Andrew, no worries! Ok, so the consensus is a LED string so far. I'll go do some research...haven't heard that term yet! I guess it's good news that it's most likely not a Main-board issue. I wasted the money on a replacement Power Supply already. Without the schematics, I'm assuming this'll be a guessing game for me to find where this is located, not to mention how to test it. Any ideas how to get Vizio to supply me with the schematics?

Bad LED strings are far from good news!

It involves tearing the panel completely down in an ATTEMPT at bypassing the LED

[AcGeorgiegirl]

Re: Vizio E470i no power

Yikes! Bad assumption, huh? I'm once again- a day late and a dollar short.

[AcGeorgiegirl]

Re: Vizio E470i no power

Ok, so if it's an LED string, I'll have to have the schematics for the panel of the tv?

[newtothis]

Re: Vizio E470i no power

Nope, Let others see what they think too before getting any deeper.

It involves removing the bezel from the edge of the panel and actually removing the LCD itself from the backlights... Its a very delicate operation and it is so easy to break the panel or bonds. Only then will you get access to the LED strings.... You MAY be able to get a string online... Most likely is you won't and unfortunately there is no markings on the individual LED's themselves so we have no way of knowing what LED to put in (If you can even get them)... To bypass will involve soldering diodes in a string and then soldering them to the pads of where the LED was (Once removed of course)

[AcGeorgiegirl]

Re: Vizio E470i no power

That sounds like trouble for me/my capabilities. Stinks! I did find a replacement set of LED"s, but it's the entire set of strings(12) and the board, so it's not cheap($49). But the other fix would mean replacing the entire panel (including strings and board), right?

[budm]

Re: Vizio E470i no power

I need good clear pictures of the bottom side of the board to see how the LEDs strings are connected together?
Is this your board? If it is then I do not need the pictures from you.
http://www.shopjimmy.com/vizio-0500-...upply-unit.htm