Vizio E420VL problem

[CraigR]

I have a Vizio E420VL and when plugged in the logo is orange and push the power button and logo turns white but that's it. Checked the power board visually and no swollen caps or signs of anything getting hot. On the underside all solder joints look good under lighted magnification. I have checked the connection and seem to have all the correct voltages at the plug. I have read on this forum before posting this about a possible EEProm problem with these main boards so was hoping the experts would chime in and give me their opinion on this or if any further testing is required.

[mu2]

Re: Vizio E420VL problem

Craig,

I wish I could help with an exact solution but I have the same set and same problem.
I bought the programmed eeprom on e-bay and it didn't fix the issue. After I replaced the chip I noticed a chip on the main board getting very hot. It is P13HDMI245-AZLE and as I recall it was near the hdmi connectors. I think I missed it in my haste.
You said that nothing was getting hot - but just double check this chip before you order the eeprom.
Mouser has the hdmi chip in stock but I haven't changed it yet.
It is possible that my set has multiple problems including the hdmi chip and eeprom.
Good luck.

Mike

[CraigR]

Re: Vizio E420VL problem

Looks ok to me right now. But thanks for the info.

[ecking767]

Re: Vizio E420VL problem

Question, when you power up your TV, can you power it off after being on for at least 30 second by press the power button?

[CraigR]

Re: Vizio E420VL problem

Logo does go back to orange after powering off.

[ecking767]

Re: Vizio E420VL problem

that tell me it may not be an EEPROM problem, can you correct a signal to the TV, or do you know the last known input that was being used?

I will try to see if there is any sound by connecting to the HDMI ports using a source like PS3, Direct TV or DVD player


or try the flash light test to the screen to see if any picture it present. like the menu once press the button?

[CraigR]

Re: Vizio E420VL problem

not sure what you mean by correct a signal to the tv and I have no idea what it was set on last but I will try hooking up a video source and see it anything happens.

[CraigR]

Re: Vizio E420VL problem

Ok I hooked a dvd player to it then cycled through the inputs and I DO have sound. I put a mag light up to the screen all over and can't see any video however.

[ecking767]

Re: Vizio E420VL problem

okay that good news, your main board is working. if you have a volt meter you will need to measure the "BL_ON" on the power supply connector.

[CraigR]

Re: Vizio E420VL problem

There is nothing marked "BL_ON" but I do have one marked "OFF_ON" and that has 3.36V but I also have one marked "LAMP" and that has no voltage.

[ecking767]

Re: Vizio E420VL problem

its seen to be your power supply inverter board that is not working. troubleshooting down to component will be complicated for me. I will replace the power supply & inverter board.

[CraigR]

Re: Vizio E420VL problem

Even though no image?? I need to repair this one so hopefully one of the Pro's will give me some advice but thanks.

[ecking767]

Re: Vizio E420VL problem

yes, to sum up, your TV power off/on, you have sound, unable to see picture because of no back-light, and BL_ON voltage is present.

measure the connection label "dim" on the power supply.

[CraigR]

Re: Vizio E420VL problem

I think I should be able to see video with a strong flashlight even though no backlight.

[ecking767]

Re: Vizio E420VL problem

I guess but not always an image can be seen on the screen using a flash light,depending on the room lighting and picture on the screen. or you could have multiple problems.

one other thing you can do is disconnect the two LCD screen cable and then power up the TV.

If you have voltage on "on/off" and "dim" pins , then your main board isn't the problem dealing with the no back light issue

[CraigR]

Re: Vizio E420VL problem

From the Tcon board? and sorry what do you mean by "dim" pins?

[ecking767]

Re: Vizio E420VL problem

From the Tcon board? and sorry what do you mean by "dim" pins?

carefully disconnect the two flat cable from the main board,then power up the TV, too see if any changes come about.

the "dim" on the power supply connector where you measure the "on/off" voltage.

[CraigR]

Re: Vizio E420VL problem

with those 2 disconnected I still have 3.2V at the ON_OFF pin

[ecking767]

Re: Vizio E420VL problem

with those 2 disconnected I still have 3.2V at the ON_OFF pin

what about the pin lable "DIM"? measure the voltage

[CraigR]

Re: Vizio E420VL problem

oops, .78v same as when they are connected.