Badcaps.net Forum
Go Back   Badcaps Forums > Troubleshooting Hardware & Devices and Electronics Theory > Troubleshooting TVs and Video Sources
Register FAQ Calendar Search Today's Posts Mark Forums Read

 
Thread Tools Display Modes
Old 10-19-2015, 08:45 PM   #1
George Request
New Member
 
Join Date: Oct 2015
City & State: Oklahoma
My Country: USA
I'm a: Knowledge Seeker
Posts: 2
Default Vizio E390 A1 issue.

This has been bugging me and I have had a hard time figuring out what I need to replace.


It powers on according to the power light, but no screen image appears.

When plugged in, the power light comes on and then fades. When I press power, the light stays on.

Once on, it cannot be turned off unless unplugged.

I cannot tell if it has audio or not.

It does not have backlights.

It does not have a picture when tested with a flashlight.


This was not a problem that occurred suddenly. This was a problem that I resolved by unplugging and then plugging back it. Over time, I had to unplug it and turn it on, unplug it and turn it on. This needed to be repeated more frequently until eventually I gave up.
George Request is offline   Reply With Quote
Old 10-19-2015, 08:57 PM   #2
budm
Badcaps Veteran
 
budm's Avatar
 
Join Date: Feb 2010
City & State: S.F. Bay area
My Country: USA
Line Voltage: 120V 60Hz
I'm a: Knowledge Seeker
Posts: 39,206
Default Re: Vizio E390 A1 issue.

Mai board problem, probably EEPROM.
http://www.shopjimmy.com/catalogsear...=Vizio+E390+A1

From shojimmy:MPORTANT:
These main boards can have multiple failures, in addition to the EEPROM.
If EEPROM replacement does not repair your board, there are likely additional problems.

Symptoms EEPROM replacement MAY fix:
- On screen display is stuck on logo screen
- TV won’t power on with remote or buttons (LED indicator remains same color)
- TV won’t turn on after being off for 30+ minutes
- TV shuts off by itself during channel scan or when switching inputs
- TV turns on and is stuck in color test pattern mode forever
- TV turns on but there is no backlight (LED indicator shows TV is on but there is no image)
__________________
Never stop learning
Basic LCD TV and Monitor troubleshooting guides.
http://www.badcaps.net/forum/showthr...956#post305956

Voltage Regulator (LDO) testing:
http://www.badcaps.net/forum/showthr...999#post300999

Inverter testing using old CFL:
http://www.badcaps.net/forum/showthr...er+testing+cfl

Tear down pictures : Hit the ">" Show Albums and stories" on the left side
http://s807.photobucket.com/user/budm/library/

TV Factory reset codes listing:
http://www.badcaps.net/forum/showthread.php?t=24809
budm is offline   Reply With Quote
Old 10-20-2015, 11:53 AM   #3
crosstalk
Member
 
Join Date: Feb 2014
City & State: Pa
My Country: Usa
I'm a: Knowledge Seeker
Posts: 56
Default Re: Vizio E390 A1 issue.

Yes, it's likely u409. There are a couple of versions of the mainboard so be sure you get the correct programmed replacement. In my case, the IC was ok but had a few bits flipped.
crosstalk is offline   Reply With Quote
Old 01-07-2019, 11:48 AM   #4
jlapage
New Member
 
Join Date: Jan 2019
City & State: Dubuque, Iowa
My Country: United States
I'm a: Knowledge Seeker
Posts: 3
Default Re: Vizio E390 A1 issue.

Anyone happen to know who makes U409? And what the pin out is as well as which leg does what (which one has voltage so on and so forth).

E390-A1. When plugged in, gets the white power light. No backlight, no audio, no picture. Have already replaced power supply board, issue remains the same. FOr the heck of it, tested all the video inputs using a Sencore Video Tester - still no video. Have heard that U409 goes bad. Also heard that EEPROM gets corrupted and that reflashing solves this issue. Main Board part number is: 756TXCCB02K042.
jlapage is offline   Reply With Quote
Old 01-07-2019, 12:02 PM   #5
nomoresonys
Badcaps Veteran
 
Join Date: Jan 2013
City & State: midwest
My Country: U.S.
I'm a: Knowledge Seeker
Posts: 7,858
Default Re: Vizio E390 A1 issue.

A bad/faulty capacitor can produce these symptoms also.
nomoresonys is offline   Reply With Quote
Old 01-07-2019, 04:10 PM   #6
Andrew F. Ali
Badcaps Veteran
 
Andrew F. Ali's Avatar
 
Join Date: Jan 2014
City & State: Point Fortin
My Country: Trinidad & Tobago
Line Voltage: 125VAC 60Hz
I'm a: Knowledge Seeker
Posts: 2,435
Default Re: Vizio E390 A1 issue.

I too have come across a faulty capacitor producing this symptom.
Andrew F. Ali is offline   Reply With Quote
Old 01-21-2019, 07:14 PM   #7
jlapage
New Member
 
Join Date: Jan 2019
City & State: Dubuque, Iowa
My Country: United States
I'm a: Knowledge Seeker
Posts: 3
Default Re: Vizio E390 A1 issue.

Bad/Faulty Cap? On the main board or power supply board? Happen to know which cap it is?
jlapage is offline   Reply With Quote
Old 04-09-2021, 02:16 PM   #8
jason123
Badcaps Veteran
 
Join Date: Oct 2015
City & State: Reno, Nevada
My Country: USA
I'm a: Knowledge Seeker
Posts: 718
Default Re: Vizio E390 A1 issue.

@nomoresonys @Andrew F. Ali
Can you please share info on this bad cap? I have the same issue, EEPROM replacement didn't fix the problem. TV occasionally turns on.

Also, does anyone have the EEPROM Dump for E390-A1 756TXDCB02K012?
Thanks

Last edited by jason123; 04-09-2021 at 02:18 PM..
jason123 is offline   Reply With Quote
Old 04-10-2021, 04:13 AM   #9
nomoresonys
Badcaps Veteran
 
Join Date: Jan 2013
City & State: midwest
My Country: U.S.
I'm a: Knowledge Seeker
Posts: 7,858
Default Re: Vizio E390 A1 issue.

Maybe check the 4 electrolytic caps closest to CN801 connector, check the capacitance and esr both if you have the tester/testers.
__________________
(Signature) One of the first and least expensive things you can do when you have an issue is take the powerboard out of the tv, flip it over and look the solder joints over with a magnifying glass if needed, add a little flux to make the solder flow well and add solder to any joints that look even a little suspect. You can practice on a scrap pcb board if needed, careful not to bridge any joints, and always let the board sit for quite a while or discharge the big caps with an appropriate resister before working on it (safety first) to try to keep from getting shocked, it doesn't take 1000 volts to KILL, a lot less can kill, so be careful, it's only a tv.

Last edited by nomoresonys; 04-10-2021 at 04:15 AM..
nomoresonys is offline   Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump



Badcaps.net Technical Forums 2003 - 2022
Powered by vBulletin ®
Copyright ©2000 - 2022, Jelsoft Enterprises Ltd.
All times are GMT -6. The time now is 04:14 PM.
Did you find this forum helpful?