Vizio E420VL problem

[ecking767]

Re: Vizio E420VL problem

DIM voltage looks ok.

your main board seen to be working, its your inverter circuit that having the problem. you have to replace your power supply & inverter board.

looking on the solder side of your power supply inverter board there is a blue LED that light up for about 2 to 3 second when you power up the TV, are you seeing the blue light?

[CraigR]

Re: Vizio E420VL problem

Yes, it comes on.

[CraigR]

Re: Vizio E420VL problem

So what can I check next?

[ecking767]

Re: Vizio E420VL problem

Order an replacement power supply & inverter board.

[budm]

Re: Vizio E420VL problem

Are you getting about 370~400VDC on the two legs of that 450VDC Main filter cap when the TV is on? You can try fixing the board or buy a replacement as eckink suggested.

[CraigR]

Re: Vizio E420VL problem

396V at the big cap. I would also like to fix this board so maybe I can learn something.

[CraigR]

Re: Vizio E420VL problem

Order an replacement power supply & inverter board.

Well got another power supply and that didn't fix squat. (other than make my wallet $50 lighter)

[budm]

Re: Vizio E420VL problem

Is this board from shopjimmy? The power supply /inverter board only requires small signals (BL_ON, DIM, PS_ON) from main board which according to the readings, you do have all the required signals for it to activate the backlights

[CraigR]

Re: Vizio E420VL problem

No not this one. But still gives the exact same problem.

[CraigR]

Re: Vizio E420VL problem

Ok, started over and found a fuse on mainboard out so got a kit from eBay that came with 2 fuses and 4 low voltage regulators and installed. Now I have orange logo then push power button and logo turns white and now the backlight flash on and off continuously. So I disconnected the main and shorted the power board and backlights stayed on like they are suppose to so I know it's in the main board however no one has one and if SJ did it's like $150 so any ideas on this main?

[CraigR]

Re: Vizio E420VL problem

turned out to be a ribbon cable from the mainboard to the top shorting and blowing a fuse. Taped up place where it was shorted and works fine now.

[ecking767]

Re: Vizio E420VL problem

which power supply did you used? the replacement?

[CraigR]

Re: Vizio E420VL problem

Did not replace the power supply or change anything on it.

[ecking767]

Re: Vizio E420VL problem

wow a bad cable, I wonder how that happen !

[CraigR]

Re: Vizio E420VL problem

On top where it went over the fram it looked to have rubbed through.

[audiofreak19]

Re: Vizio E420VL problem

Ewww. That sucks. Yea when I get a new tv and if there is any kind of a possibility that it might be a main board or power supply I always check any and all fuses I can find. Rule out the easiest stuff first. Then I try looking at voltage regulators. Just an idea for next time to try and avoid buying a board and have it not fix the problem even though in this case it did sound like it.