Vizio E220VA no standby, no power

[cguzek]

Hi, purchased tv broken off craigslist with hopes of power supply being dead.

I got tv, opened up, and have all outputs on power supply have voltage. The both 5.2v rails are reading 5v, and both 16v rails are reading 17.8, thought this may have something to do with it. (ordering all through hole nichicon capacitors for both power and main board) Was surprised to see any voltage at all on 16v rail since tv's i've fixed in the past usually only have 5v rails and standby rail on, but higher rails usually turn on after power button is hit i thought.

I was looking to see if anyone else had the problem, and didn't find much other than an ebay auction offering to repair the main board to fix the no power problem. I'd love to fix mainboard myself instead of pay someone to do it for me, but not sure what it could be. checked all the larger surface mount voltage regulators, and seems from their datasheets that they are working properly. couldn't find any fuses on mainboard. If anyone has any ideas, please let me know.

[budm]

Re: Vizio E220VA no standby, no power

This is just basically a 22" monitor with TV tuner, so it does not use standby power supply, they are always on power supply. They just turn off the inverter circuits and the power to the LCD panel T-CON board when unit is in standby.
So how about showing us the picturwes of the board, especially the LDO regulator ICs.

[cguzek]

Re: Vizio E220VA no standby, no power

Sorry, not the best quality, need more AA batteries for my digital cam, this are pics with my camera phone. If there is a place that needs to be zoomed more and clearer, let me know. looking for some batteries.

[cguzek]

Re: Vizio E220VA no standby, no power

also, there are some voltages going to both the on/off/volume switch little board, and the led/ir receiver little board.

[martyparish]

Re: Vizio E220VA no standby, no power

There should be some surface mount fuses. Look very closely for anything labeled F1, F2 etc...

[cguzek]

Re: Vizio E220VA no standby, no power

haven't been able to find anything with just an f yet, found some labelled fb, but i believe thats ferrite bead. Just checked top and bottom for a second time, all smd components, and cannot find a single fuse on the main board.

[selldoor]

Re: Vizio E220VA no standby, no power

As I am sure you have guessed the pictures are useless for troubleshooting.

[cguzek]

Re: Vizio E220VA no standby, no power

yes, was pretty sure pictures weren't helpful, but as i said, i needed batteries for my reg camera. figured some pics were better than none. Here are the pictures so you can zoom on each component and see what it is.

[selldoor]

Re: Vizio E220VA no standby, no power

Ok Pictures are very good - I cant see any fuses either.
Can you do a straight on picture of the power supply top and bottom.
and one of the bottom of the main board.
I cant see that you have actually said what is the fault with the TV.
With a source signal connected can you tell us what happens - on plug in - on switch on - up to the final fault stage - What does the power light do - does the screen flash
any noises - any sound

[cguzek]

Re: Vizio E220VA no standby, no power

Ok, when I plug it into outlet, i get no standby light, and pushing power button does nothing. Nothing on screen, no flashes, no led standby light.

Power supply has 5v and 17.8 volts going out where it says 5.2v and 16v.

[selldoor]

Re: Vizio E220VA no standby, no power

OK - There should be more boards with the inverter transformers on and also the TCON or panel board - can you post pictures of those

[cguzek]

Re: Vizio E220VA no standby, no power

seems like just three boards, and the little one that goes to the standby led and ir sensor. The top board that's connected with ribbons to the lcd panel is getting no voltage at all.

[selldoor]

Re: Vizio E220VA no standby, no power

heh heh Its a LED lit panel so no inverters - re-think required!!

[selldoor]

Re: Vizio E220VA no standby, no power

At last - in pic 4 and5 there is a small white fuse with a "K" on it - can you test it
POWER OFF
meter on ohms

[cguzek]

Re: Vizio E220VA no standby, no power

Sorry, i should have specified it was an LED, sorry. From what i've looked up, it seems to be something wrong with the main board. There is a company that charges like 75 to ship in main board and fix, but i'd rather not pay that much, tv isn't worth it to me unless I can fix it. Although I will be changing electrolytic caps on both boards especially on power supply board considering the 17.8 voltages it is putting out seem a tad high for it saying 16v on the board.

[selldoor]

Re: Vizio E220VA no standby, no power

The voltages will be high because there is no load to pull it down. Usually only the lower voltages are regulated.

[cguzek]

Re: Vizio E220VA no standby, no power

Fuse marked K, on the panel board is testing good. That board doesn't even get any power when tv is plugged in.

[selldoor]

Re: Vizio E220VA no standby, no power

Pity I like a blown fuse - something easy to fix

So need to find where the voltage to the board comes from and why its not there.
Start at the fuse with the k and find which pins the trace goes to. Find which wire/s go to that pin and find the pins on the socket at the other end of the cable. Find where they connect at the main board an trace back from those pins on the main board.
Also which socket goes to the led lights.

[budm]

Re: Vizio E220VA no standby, no power

You will not get anything on that fuse since it is fed by switched transistor which is turn on by the main board. I can see some 3-pin regulator IC's. Please take the voltage readings per instructions on the link below my signature.
What voltage do you have on CN902 ON/OFF, DIM PINS?

[cguzek]

Re: Vizio E220VA no standby, no power

On DIM pins on CN902, I have 0.00v for both on/off pins.

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