Vizio M420NV problems

[mcross]

Ok heres one for you. got this vizio M420NV LED TV.
powers on to logo screen then off, cycles on and off a few times by its self, then stays on logo screen, but just stays there. can not turn off, remote will not power on or off, button will not ether. have to unplug.
mike

[tom66]

Re: Vizio M420NV problems

Corrupt EEPROM/flash chip. Replacement chip I think is about $25.

[mcross]

Re: Vizio M420NV problems

thanks will try that
Mike

[mcross]

Re: Vizio M420NV problems

I found a main board cheap, but has a reversed picture, is that a setting? never seen before
Mike

[mcross]

Re: Vizio M420NV problems

Tom, I had a thought and heated the main board witha heat gun and it came on , went to the menu, ect.. , would you still think eprom?

[attainteddragon]

Re: Vizio M420NV problems

i have heard of vizios with a non shut down issue caused by a stuffed voltage regulator on the main! always worth a look!

[tom66]

Re: Vizio M420NV problems

Probably not EEPROM then. Processor could have BGA failure, like Xbox 360 RROD.

[mcross]

Re: Vizio M420NV problems

Main board has a regulator u4 1117 reads pin 1 0.00 pin 2 1.00 pin 3 3.10 is that right?

[tom66]

Re: Vizio M420NV problems

Doesn't seem right. Double check readings, also can you get full part number e.g. AK1117-33.

[johnboy1313]

Re: Vizio M420NV problems

I've read that reflowing the IC (the same one that seems to get the corrupt EEPROM) sometimes fixes these. Maybe you have a cold solder joint somewhere.

[mcross]

Re: Vizio M420NV problems

Its good, had my meter on 200v reads pin 1=0.00 pin 2=1.24 pin 3=3.35
part number is OFf 1117 no other #s on on it

Also did you see my post about the reversed picture ? found a cheap main board but pic is reversed?

[tom66]

Re: Vizio M420NV problems

Output appears correct then.
May be possible to fix reversed picture if you can get into service menu.

[mcross]

Re: Vizio M420NV problems

Tom,
Would i need just the regular remote to do that?

[tom66]

Re: Vizio M420NV problems

I don't know if these Vizios even have a service menu....

[richpart]

Re: Vizio M420NV problems

Verify both old and new eeprom numbers are exact match. I used an eeprom for testing once that was close but not exact and it produced a reversed picture.

[SgtRock]

Re: Vizio M420NV problems

Dear Mcross:

--You can get a M420NV Manual here:



"Measure twice. Cut once"
Norm Abram 1950 -

Best Regards
Clear Ether