Vizio E470Vl no backlight problem

[budm]

Re: Vizio E470Vl no backlight problem

Which one goes to main to activate BL/ON?

Show us the pictures of your power supply board and a closed up of the connector on the power supply board that goes to the main board.
Are you having BL-ON control signal from main board problem?
What is the TV not doing?

[Wirenut420]

Re: Vizio E470Vl no backlight problem

It was indeed too low of a voltage to activate the backlights. I had the member just jump the PS-ON to the BL-ON pin and snip the wire going to the main board that activates BL-ON. For now, he's watching the TV again with no money spent.

Which one goes to main to activate BL/ON?

[aaronwt6]

Re: Vizio E470Vl no backlight problem

It was indeed too low of a voltage to activate the backlights. I had the member just jump the PS-ON to the BL-ON pin and snip the wire going to the main board that activates BL-ON. For now, he's watching the TV again with no money spent.

[aaronwt6]

Re: Vizio E470Vl no backlight problem

I know this is an old thread but I'm trying to help out an eBay member with a no backlight issue on this same model. His BL-ON signal is 1.32V and I'm wondering is that's the issue. What is typically enough to activate the backlights? I would think it should be more in the 2.5V - 3V range so I'm thinking he's got a main board problem.

Any opinions are greatly appreciated.

[triplefour]

Re: Vizio E470Vl no backlight problem

so uhh.. what ever happened here?

[budm]

Re: Vizio E470Vl no backlight problem

That is the dual MOSFET:
https://cdn.badcaps-static.com/pdfs/...e9f2435410.pdf

[chandonh]

Re: Vizio E470Vl no backlight problem

yep the top line reads 4953gm.the bottom line reads a07014-thanks again for your help. i will post results when i get the part replaced..

[budm]

Re: Vizio E470Vl no backlight problem

I am curious as to what the U33 is, can you read any printing top the of the body?

[chandonh]

Re: Vizio E470Vl no backlight problem

thanks bud-you're the best-got the parts ordered and my fingers crossed-sorry i'm such a newbie

[budm]

Re: Vizio E470Vl no backlight problem

Vizio 3647-0292-0150 is your main board based on the number as printed on barcode.
http://www.shopjimmy.com/vizio-3647-...or-e470vl.htm#

http://www.shopjimmy.com/vizio-3647-...repair-kit.htm



Per description from SJ:
The Vizio 3647-0292-0150 Main Board Component Repair Kit includes all necessary components to repair common failures on the Main Board. Symptoms include stuck or frozen at the Vizio welcome screen, TV turns on when you press the power button but has no backlights.

Part 2

Symptoms:
No Backlights
Description Quantity Board Location
Integrated Circuits 1 U33

You may want to look at U33 to get the P/N as printed on top of the IC to see what it is what its function is.
Pictures provided by shopjimmy.

[chandonh]

Re: Vizio E470Vl no backlight problem

WTF! Really? Lest see now I do not have the exact same board in front of me to trace, that is right, I have done many tracing and reverse engineering many time before for lots of people here for FREE by spending many hours of my own times!
So good luck with your repair if you do not want to do some work.

wow i was just asking if anyone knew where to start like what components to check first.sorry i blew up at ya i guess

[chrismurphy]

Re: Vizio E470Vl no backlight problem

https://cdn.badcaps-static.com/pdfs/...2234c11cc4.pdf

[budm]

Re: Vizio E470Vl no backlight problem

I signed up for this forum for help not to be told to find the problem and fix it yourself.

WTF! Really? Lest see now I do not have the exact same board in front of me to trace, that is right, I have done many tracing and reverse engineering many time before for lots of people here for FREE by spending many hours of my own times!
So good luck with your repair if you do not want to do some work.

[chandonh]

Re: Vizio E470Vl no backlight problem

does anyone know where to buy the 1117 voltage regulators for this tv,thanks

[chandonh]

Re: Vizio E470Vl no backlight problem

I signed up for this forum for help not to be told to find the problem and fix it yourself.

[budm]

Re: Vizio E470Vl no backlight problem

well i was hoping someone would give me an idea what to check without spending hours looking at traces.i have voltage throughout the board but it just isn't enough to kick on the backlights

Unless you have the diagram of the main board, then yes, it is VERY time consuming.

[chandonh]

Re: Vizio E470Vl no backlight problem

well i was hoping someone would give me an idea what to check without spending hours looking at traces.i have voltage throughout the board but it just isn't enough to kick on the backlights

[ecking767]

Re: Vizio E470Vl no backlight problem

you need to trace out the back-light signal path using a multi-meter in the continuity function. I had this problem before and I remember some caps and resistors make up the circuit and then to the main processor.

if those caps and resistor are good then its the processor failing to send the voltage to turn on the lamps

you will need magnifying glass 10x or better

[chandonh]

Re: Vizio E470Vl no backlight problem

Desperate for help

[chandonh]

Re: Vizio E470Vl no backlight problem

any help