Vizio E500i-B1 - Powers on then fades out - Works if left unplugged for an hour or so

[Doc38343]

Re: Vizio E500i-B1 - Powers on then fades out - Works if left unplugged for an hour o

OK ordered freeze spray but meanwhile I decided to try and turn it on today. It came on so i read the voltages.
PS-ON is 2.96v
ON/OFF is 3.3v
Dim is 2.8
12volt rail is 12.6v
HOWEVER the 24v rail is only 15.6v (I am surprised it is even working but I have a normal looking picture right now)
Does this shed any light on situation? Short? or power supply?

[budm]

Re: Vizio E500i-B1 - Powers on then fades out - Works if left unplugged for an hour o

When it acts up again then take the readings to see what you have.
I will have to look and see how the 24VDC is generated.

[dick_barton]

Re: Vizio E500i-B1 - Powers on then fades out - Works if left unplugged for an hour o

While it's on can you go into the service menu and see if it indicates what is causing the power up problem.

[budwich]

Re: Vizio E500i-B1 - Powers on then fades out - Works if left unplugged for an hour o

check / replace cap's associated in and around the 24v stuff.

[budm]

Re: Vizio E500i-B1 - Powers on then fades out - Works if left unplugged for an hour o

Per your post #7:
Right side connector:
Red 5.12 and orange 5.12
NC - NC
Blk 0v and bro 0v this rail is 12v when working
Grey 0v and whi 0v this rail is 24v when working
Blue /Violet 0v ground rail
Yellow /Green 0v ground rail
Red 0v - is 3.3V when working -PS-ON
Blk 0.26v and Brown 0v DW and ON/OFF
You were getting 24V before.
The 12V and the 24V are driven by the same drive in the primary side.

[Doc38343]

Re: Vizio E500i-B1 - Powers on then fades out - Works if left unplugged for an hour o

OK just getting more puzzled..... (still waiting for the freeze spray to come)
OK has been unplugged for couple of days so I plugged it in and fired it up again.
Same thing it comes on and works fine, except the 24v rail is 15.6
So i let it play for 15min and then shut it off and turned it right back on. It came up again so i looked in the menu but learned nothing. then i shut it down and turned it back on again. Same thing it worked again.
I decided to check various check points but all are same as before. Then I shut it down and started checking test points when i noticed something different this time, the 24v rail is still powered with 15.6v.... It did not drop like it was before.
Before if I checked it when I tried to turn the TV on it would rise to 12v and then drop back down to 0.06 or so. I am now waiting to see if it trips off and drops back to 0.
Still just want to know... power supply or main board?
Which board turns that rail on and off?

[Doc38343]

Re: Vizio E500i-B1 - Powers on then fades out - Works if left unplugged for an hour o

While I was typing last post it went to 0.0v... still plugged in. Also the damn thing turned on again. This is the most aggravating one I've ever worked on. Why is it now working after a few days ago it wouldn't work at all even when unplugged for a long time.
I am out of my depth and hand shakes so i have a hard time getting reading on any tight places. Don't want to short anything Perhaps the freeze spray will reveal something not seen.
Still don't get WHY is it working now? I literally haven't changed anything, only thing i did do was remove plugs and reconnected. I also took the power supply off the set and examined the back side and tested the diodes . Could it have been a ground?
15.6 on a 24V rail is pretty far off so something is pulling it down somewhere.
Much easier when a set dosen't work at all... LOL

[Doc38343]

Re: Vizio E500i-B1 - Powers on then fades out - Works if left unplugged for an hour o

Per your post #7:
You were getting 24V before.
The 12V and the 24V are driven by the same drive in the primary side.

Thanks Bud but i am not sure on that i had a helper here the first day and he told me it was "normal" so i assumed he meant it was 24v sorry for that misinformation.
I now suspect it was actually 15.6 then as well.
I started testing it when it was in a failed state and while it was off.
First time i got it to turn back on was when i got the first reading of 15.6.

D.T.A.... don't trust anybody.. do it yourself.. LOL
Sadly there is only one me and nowhere near enough hours in a day.

[Doc38343]

Re: Vizio E500i-B1 - Powers on then fades out - Works if left unplugged for an hour o

While it's on can you go into the service menu and see if it indicates what is causing the power up problem.

I don't have a service manual, it is working right now can you tell me how to get to the service menu?

[Doc38343]

Re: Vizio E500i-B1 - Powers on then fades out - Works if left unplugged for an hour o

After I left it plugged in all day today it now will not turn on again.

Freeze spray comes on monday I hope.. I will try and see if a part heats rapid or locate the one holding...

DAMN I am thinking just buy a power supply and eat the restocking fee if it is not the trouble..

[Doc38343]

Re: Vizio E500i-B1 - Powers on then fades out - Works if left unplugged for an hour o

Freeze spray was a wash out couldn't tell anything. the heated chips were the same as keep standby going and I have a fluke digital laser thermometer and all the chips on the visible side are within normal parameters.
I ordered a complete repair kit from S.JIMMY for a very reasonable price that has power supply/main board/T-con all included. I will change only one at a time to see which one is the real culprit for future reference and then post the result here.
What a pain in the butt this has been. Perhaps I can help the next guy with one of these SUPER HIGH QUALITY (sic) Vizio TV's
I actually think it is the main board but we will see. Shipping target is July 5th so back later, and thanks to all who tried to help me with this.

[Doc38343]

Re: Vizio E500i-B1 - Powers on then fades out - Works if left unplugged for an hour o

Update:
Got the total repair kit so I decided to change one board at a time to find the source of the issue.
Changed motherboard... no changes in voltages and problem still existed.
Replaced original MB.
Changed power supply. Has worked consistently for 3 days now.
Power supply was the source of this issue.
Noticed voltages only slightly different like only .02 of a difference max.
Decided to change the MB again to see if the 15.6 on the 24v rail changed.. it did NOT Change.. still 15.6.
The change I did find is simply this:
on the new power supply when you turn the set off the PS-ON and the ON/OFF pins instantly go to 0v.
On the old one in failed state they would stay on and bleed down very slowly.
On the old one they always had .06v or more unless unplugged for a very long time.
New PS goes to 0.01 almost instantly.
Also noted that the set powers on noticeably faster.

A switching transistor small one or a diode was likely the failing part. I still don't know which one but since all the top side devices seemed ok I suspect the failing part to be a SMD component on the bottom side of the board.

I am done with this one. Full repair kit was only $15-$20 more than the single board. TV works great again.

Thanks for all the input.
Doc

[jhrsmail]

Re: Vizio E500i-B1 - Powers on then fades out - Works if left unplugged for an hour o

I am done with this one. Full repair kit was only $15-$20 more than the single board. TV works great again. Doc

Wow, I would like to know where you got a full repair kit for that price! I've replaced the power board (107.00) and the main board (80.00) and still no fix. I've returned both of the boards for refund, so back to square 1!

[Doc38343]

Re: Vizio E500i-B1 - Powers on then fades out - Works if left unplugged for an hour o

I bought it from shop jimmy. they called it a "full repair kit" was just all the boards out of a broken screen tv i'd suppose.
Sorry not more help here... it has been a minute.

[jhrsmail]

Re: Vizio E500i-B1 - Powers on then fades out - Works if left unplugged for an hour o

DO you still have the TV? Still working? I have the same problem, 15.3VDC on 24VDC leg. I've changed main and power board, then bought IC9101, and IC9301 and replaced them. It worked for a while with the IC9301 replacement, but I was still getting 15.3VDC. I'm not sure where to look now.

[Doc38343]

Re: Vizio E500i-B1 - Powers on then fades out - Works if left unplugged for an hour o

DO you still have the TV? Still working? I have the same problem, 15.3VDC on 24VDC leg. I've changed main and power board, then bought IC9101, and IC9301 and replaced them. It worked for a while with the IC9301 replacement, but I was still getting 15.3VDC. I'm not sure where to look now.

TV is still working....
Even with the repair board replacements my 24v rail still only read 15.6v when under load. This TV belongs to a customer but he said was working fine still.

[Serfma]

Re: Vizio E500i-B1 - Powers on then fades out - Works if left unplugged for an hour o

Update:
On the old one in failed state they would stay on and bleed down very slowly.
On the old one they always had .06v or more unless unplugged for a very long time.
New PS goes to 0.01 almost instantly.
Also noted that the set powers on noticeably faster.

I'm newish to troubleshooting TVs and bought the exact model with the exact problems. Previous owner said it'd only turn on after a few hours. When you say always had .06v on the two pins, was this while the TV was unplugged and tested, or plugged and switched off and measured without the connector plugged in?

I know to be very very careful if you don't know what you're doing which is why I'm curious and asking before testing as I think I have the same exact problem now.

[Ward Thomas]

Re: Vizio E500i-B1 - Powers on then fades out - Works if left unplugged for an hour o

I have 3 of these TV's in Cozumel MX. All 3 have the same problem you describe. I have replaced the MB on one of them and it's still working fine but has not been that long with the new board. Wondering if anyone ever figured out what the bad component is that causes the problem?