Vizio E260MV - No power or standby light

[Grey]

Vizio E260MV
Main board: 796431300500r (492A016M1300R)
Power supply: ITPI-008 / 790041400500R
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This TV went dark on us, so I am trying to bring it back to life. I have not been able to find any service manual or schematic for this set. Also, the pin outs on the power board only have a 1 and 15 to designate pin numbers, so don't know which pins do what.

I have looked over the power board for any obvious bad caps or whatever... all looks fine. I tested the pin outs(tv off) and got these numbers...
1. 13.41v (this is the only wire that is red, others are black)
2. empty
3. 13.41v
4. ground
5. 12.25v
6. 5.51v
7. ground
8. 5.50v
9. 5.50v
10. ground
11. ground
12. 3.42v
13. .08v
14. .30 - .50v
15. ground

I inspected the main board and found some obvious problems. It appears that a voltage regulator(U7204) and a ferrite bead(FB7205) have both been fried. The regulator is damaged such that I can't get all the numbers from it and have been unable to locate even the correct manufacturer. What I can see, if I get the light and magnifying glass just so, are tall thin letters "AX", followed by at least 3 numbers of which the 1st 2 appear to be "66". Next line look like a smaller "A" then a blemish, then I think "18". Next line appears to be 1118, but may have more after it. The middle pin is the type that is cut and not connected to the board. The other regulators on the board are of different types.

I tested the regulator and the right pin(pin 3) shows voltage that seems to correspond to pin 14 coming from the power supply. The other 2 pins show no voltage.

Would anyone by any chance have one of these boards and can tell me the numbers off the regulator at U7204? Also, how do I determine what replacement to get for the ferrite bead?

I appreciate any help.

[budm]

Re: Vizio E260MV - No power or standby light

So the ferrite bead is blown open? And what dcv do you on all 3 pins of that regulator? What resistance do you have between GND and each end of the freeite bead?
The output pin (big tab) feed the ferrite bead which feed the Voltage to IC3103, so look up the P/N of the IC3103 to see what Voltage it needs to run the IC. Something is shorted on the output side of the ferrite bead which you need to find out where the shorts is.

[Grey]

Re: Vizio E260MV - No power or standby light

Thanks for the response.

The voltage reading of pin 3(right) was @3.3v on the first reading, but then all subsequent readings were .2-.3v(<1v). the other pins and the tab are all 0v.

The ground to ferrite bead reads .9ohms on each end.

The IC at U3103 is Hynix H5PS5162FFR-26C. It's a 512Mb DDR2 SDRAM chip and expects 1.8v.

I thought maybe the voltage regulator just failed and bled out high voltage long enough to blow the ferrite bead. You think it's something beyond the bead that blew them both? I guess I'm confused about how the bead works since it has some connection to ground. It acts like a filter? Could it have failed and caused the short?

The Mediatek chip looks a little gunky to me now too(added 2 photos). Can that even be replaced by a hack solderer like me? Any tips on checking those chips or any other "most common causes"?

[budm]

Re: Vizio E260MV - No power or standby light

The load side of the ferrite is where the problem is, you are getting 0.9 Ohms and GND so you need to find out of the IC3103 is shorted or the filter cap is shorted. The output of that 1.8V regulator may also go somewhere else beside IC3103.
The ferrite bead is just a very small inductor and connected in series to the load.