Vizio E470VL NO Backlight help

[budm]

Re: Vizio E470VL NO Backlight help

TV Off. TV On
DIM. 0. 3.3
Lamp. 0. 0
I-On/off. 0. 3.3
PS_On. 0. 2.3

12V. 0. 12.3
0. 12.3
0. 12.3

SGND. 0 0
0. 0
0. 0
0. 0

+5VSB. 5.2. 5.2
5.2 5.2
5.2. 5.2

You do have the command signals to turn on the backlights circuit, and if you do not even see the backlights flash on for second before going into shutdown then you need to start looking in the inverter section starting by to see if there is any fuse/fusible resistor for feeding the Boosted B+ to inverter section or not, visual inspection, etc. just use logical step in troubleshooting.

[Anthony M]

Re: Vizio E470VL NO Backlight help

Your last post I think is a little over my head. Inverter board. Is that the small one

[Anthony M]

Re: Vizio E470VL NO Backlight help

I looked at those posts you sent me , for a novice their a
Little intimating. Is the Next step to test the bulbs, and inverter. I was reading some more. And I think my power board has the inverter built on it...

[budm]

Re: Vizio E470VL NO Backlight help

your board is the power supply-inverter board combo. The drive Voltage for the inverter Transformers's primary windings are about 400VDC and driven by power MOSFET.
What ever the failure is, it can turn out to be SMD (Surface Mounted) parts so I hope you can deal with that if the needs arised.

[Anthony M]

Re: Vizio E470VL NO Backlight help

Would you recommend I just replace the board. Is that a good option. I don't feel I have the knowledge to replace circuits , but I am always willing to give it a shot.

[vinceroger69]

Re: Vizio E470VL NO Backlight help

it could be the psu/invetor board but also maybe a bad ccfl lamp in the panel assembly do you see a flash on the screen when you turn the set on? it may be fast like 1 to 2 seconds

[Anthony M]

Re: Vizio E470VL NO Backlight help

Ok, I checked what you said. I clicked on the TV and the screen flashed for about a sec.

[vinceroger69]

Re: Vizio E470VL NO Backlight help

can you post a good clear picture of the back of the power supply as you may need to check the invertor transformer windings next for shorts are there any numbers on top of the two transformers that are by the back light wiring connectors.

[Anthony M]

Re: Vizio E470VL NO Backlight help

So you want me to take the board off and take pic of the soldered side..

[budm]

Re: Vizio E470VL NO Backlight help

Please verify if this your board.
Vizio 0500-0407-0700 Power Supply / Backlight Inverter
http://www.shopjimmy.com/vizio-0500-...upply-unit.htm
Since you did see the backlights flash on for seconds, then it can be the inverter circuit or the lamp/s problem.

[Anthony M]

Re: Vizio E470VL NO Backlight help

Yes that is board that I have ...

[Anthony M]

Re: Vizio E470VL NO Backlight help

Replaced the board . Still no backlights . Just tore it down and inspecting the bulbs

[vinceroger69]

Re: Vizio E470VL NO Backlight help

with the lcd panel and diffuser sheets removed you should still be able to power on the tv and see if all the ccfl tubes flash