Vizio E55-C2, appears dead, no 20V, main cap always 385V, no PSon

[dick_barton]

Re: Vizio E55-C2, appears dead, no 20V, main cap always 385V, no PSon

I'm having a hard time seeing the board, it is pin 8 its in circuit with. Its callout is VIN, input voltage supply pin.

I think that it may be Pin 4 (Soft Start) and not Pin 8. The data sheet shows pin 1 on the slanted side of the IC which unfortunately I cannot tell from the photo, however Pin 5 is ground so that would confirm whether it's pin 4 or Pin 8.

Looking again at the photo it does look as though it's Pin 5 and the data sheet does show 2 x 10uF caps connected to it.

[R_J]

Re: Vizio E55-C2, appears dead, no 20V, main cap always 385V, no PSon

If you look at the white outline you will see a small notch mark at one end, also there is a larger white mark marking pin one. It is more noticeable on other ic's on the board like XP1

[dick_barton]

Re: Vizio E55-C2, appears dead, no 20V, main cap always 385V, no PSon

RJ, well spotted.

[DXseekerMO]

Re: Vizio E55-C2, appears dead, no 20V, main cap always 385V, no PSon

I see a "wedge" on one side of U2. On that same side there's a thick white line on the board. I took that as the number one pin right next to the thick white line.

[petehall347]

Re: Vizio E55-C2, appears dead, no 20V, main cap always 385V, no PSon

notched side same as line on ic . what is this wedge you talk of ? p.s yes that is pin 1 .
on another note some isc.s have an indentation but not important right now .

[DXseekerMO]

Re: Vizio E55-C2, appears dead, no 20V, main cap always 385V, no PSon

petehall347, by wedge I meant an angle cut in at the top edge of the U2 eeprom.

If I read the datasheet right the pins are

1 2 3 4

8 7 6 5

[petehall347]

Re: Vizio E55-C2, appears dead, no 20V, main cap always 385V, no PSon

pin one top left notch at top is how it is on rj.s post

[DXseekerMO]

Re: Vizio E55-C2, appears dead, no 20V, main cap always 385V, no PSon

lol I did get them backwards. Should have been:

4 3 2 1

5 6 7 8

Making pin 8 in-circuit with the defect.

[DXseekerMO]

Wire bypass installed, end result.....

I installed a strand of copper wire from what is left of the trace to the small cap off leg 8. End result:

[DXseekerMO]

Re: Vizio E55-C2, appears dead, no 20V, main cap always 385V, no PSon

So after taking time to test the TV and its functions it looks like it's going to be a winner! Everything works fine on it.

This was a great learning experience....and my first "repair" of a main board. I probably won't fix this one all the way since I don't have a microscope to see with. My eyes aren't what they used to be and I don't want to accidentally do a half duff job and not see it.

I'm sure glad the rest of the TV is good, I drove a total of 180 miles to get it.

My thanks and appreciation to R_J, dick_barton, petehall347 and budm for your time and all the great info/direction! Getting this far wouldn't have happened otherwise and I wouldn't have learned a thing.

[DXseekerMO]

Re: Vizio E55-C2, appears dead, no 20V, main cap always 385V, no PSon

So I received the new main board I ordered today, unfortunately the number on it checks to a D65-D2. The boards look identical. I was just wondering if there's any way to install it and set it up in the service menu for use in this TV?

[R_J]

Re: Vizio E55-C2, appears dead, no 20V, main cap always 385V, no PSon

I don't know, checking Shopjimmy site, it looks like E55 and D55 use the same board and the E65 and E55 use the same, It looks like there are additional backlight fets on the 65" board, so It might work in the 55" but there may also be different firmware etc. on the board.

[DXseekerMO]

Re: Vizio E55-C2, appears dead, no 20V, main cap always 385V, no PSon

That's what I suspect too, different firmware. I didn't compare the two closely as I'm trying to finish up a Mercedes R171 project for someone.

The good news tho is I now have a brand new main board for a D65-D2 and only paid $21.00 for it. Now to find one.....

Thanks again R_J, I appreciate it!

[DXseekerMO]

Re: Vizio E55-C2, appears dead, no 20V, main cap always 385V, no PSon

I think I can close this out now. Earlier this week I ordered a MB for a D55-D2, installed it and it passed quality control inspection. I also ordered a new remote and feet for it off fleabay.

[captainKKK]

Re: Vizio E55-C2, appears dead, no 20V, main cap always 385V, no PSon

Fat chance you still have and will part with the D65-D2?