Stinky Vizio VO370m No menu or picture.No voltage to T-con

[allsmith]

Found in landfill,actually it was really clean and not stinky at all lol...

Well here is what i have come up with...Vizio light goes from orange to white and the backlights do come on but its still just a black screen,well sorta dark blue from the backlights bleeding around edges...pushing buttons on side do nothing..no menu or anything comes up on the screen..The power button does work and tv will turn off if i turn it off.

I tried all hdmi inputs with a dvd player and nothing,but i did get sound at one point but lost it pushing buttons and couldn't get the sound to come back.

I've searched about all i can find on this tv and did see another case of one on here that another fella had and he was checking the voltage regulators on the main board...so i have done that and will post up my findings. Also i have read about Vizios having the Eeprom problem but that seems to be more towards the (E) series vizios.

Anyways i have 12VDC and 5VDC at both fuses on main board...both sides of fuses but i do not have any voltage at the fuse on the T-Con board

Here are my findings on the voltage regulators on the main board..they all seem real close but im not good enough at math to figure out if there within tolerance or not...sorry high school drop out.lol...i've seen Retired Caps tutorial on voltage regulators and seen the math he did to figure out if there in tolerance but mine are so close and even with a calculator i cant make out what all the numbers mean! lol

I've also seen a post by Budm saying if there is no voltage to T-con we need to look for the SMD mosfet on the main board so i suspect thats where i might have to go if the voltage regulators are within tolerance..

Thanks guys any help would be appreciated!

U2
L161
G1117
pin 1 = 2.05
pin 2 = 3.29 ...1.25 + 2.05 = 3.3
pin 3 = 4.98

U4
L161
G1117
pin 1 = 2.04
pin 2 = 3.29 ...1.25 + 2.04 = 3.29
pin 3 = 5.01

U5
L161
G1117
pin 1 = 1.372
pin 2 = 2.62 ...1.25 + 1.372 = 2.62
pin 3 = 4.98

U7
L227
G1084
pin 1 = 2.03
pin 2 = 3.27 ...1.25 + 2.03 = 3.28
pin 3 = 4.98

U8
L161
G1117
pin 1 = .001
pin 2 = 1.247 ...1.25 + .001 = 1.251 *Is this out of tolerance?
pin 3 = 3.26

U9
L161
G1117
pin 1 = 1.256
pin 2 = 2.49 ...1.25 + 1.256 = 2.50
pin 3 = 4.98

U11
7805ct
Rau828g
pin 1 = 12.02
pin 2 = 0 Fixed
pin 3 = 5.00

[dick_barton]

Re: Stinky Vizio VO370m No menu or picture.No voltage to T-con

Budm refers to a mosfet on the mainboard close to the LVDS connector that switches the 12V to the Tcon. Have you checked the mosfet?

[budm]

Re: Stinky Vizio VO370m No menu or picture.No voltage to T-con

There are 3 fuses on that main board, the third fuse is a small black fuse with 'N' printed on top, the designator for that fuse is TF1.
It is on the left of F2 in your 4th picture

[allsmith]

Re: Stinky Vizio VO370m No menu or picture.No voltage to T-con

There are 3 fuses on that main board, the third fuse is a small black fuse with 'N' printed on top, the designator for that fuse is TF1.
It is on the left of F2 in your 4th picture

Thanks Budm,I didnt know that...I just checked and TF1 appears to be open with 12VDC only on one side. I'll wait for you to tell me what my next step should be..thank you!

[allsmith]

Re: Stinky Vizio VO370m No menu or picture.No voltage to T-con

Budm refers to a mosfet on the mainboard close to the LVDS connector that switches the 12V to the Tcon. Have you checked the mosfet?

No i have not..actually im not sure were the mosfet is yet..I'll see if i can figure out tonight..thank you...Will the mosfet be a 8 pin or a 3 pin?

[dick_barton]

Re: Stinky Vizio VO370m No menu or picture.No voltage to T-con

You'll need to replace the fuse TF1 since that may be the only problem you may have.
In the meantime you could check the open side of the fuse to chassis with your meter to ensure there is no short circuit at that point.

[budm]

Re: Stinky Vizio VO370m No menu or picture.No voltage to T-con

you'll need to replace the fuse tf1 since that may be the only problem you may have.
In the meantime you could check the open side of the fuse to chassis with your meter to ensure there is no short circuit at that point.

+1

[allsmith]

Re: Stinky Vizio VO370m No menu or picture.No voltage to T-con

Thanks..i just checked resistance from ground(chassis) to the dead side of the fuse (tv off) and i get initially about 100 K ohms and then is steadily falls to and stays at 17 K ohms...

The fuse is marked N is this what they call a ''thin film'' smd fuse? and N is the amperage rating?..From what i can tell is (N) is a 2amp fuse by littelfuse,but i see quite a few different series of them...Does this look right here at Mouser?
http://www.mouser.com/Search/Product...yFR9RKLQ%3d%3d

Im trying to find one on junk boards i have laying around and so far no luck..but i'll have everything tore apart later tonight looking for one..Haha

[allsmith]

Re: Stinky Vizio VO370m No menu or picture.No voltage to T-con

Guys im a little confused about what size and style fuse TF1 is.. Does the TF1 designation on my board mean Thin Film 1 amp or does the (F) stand for fast blow?..I have a (N) fuse at the TF1 designation and (N) stands for 2 amp that i can tell on Littelfuse website.

I looked at a bunch of junk boards tonight but i couldn't find anything..I did find a fuse marked 20 with a board designation of F1A..and i seen a post by Tom66 saying that is a fast blow 1 amp...but the fuse says 20, so can you see my confusion..lol..

Anyway here is a pic of a fuse i found on a junk inverter board,do you think that is a 1amp or a 2amp?..I wouldn't think its a 20amp..Think it would work?

Also in my last post is a link to what i think is the correct fuse from Mouser can you look and see if its correct for my application? Thanks! Oh also in my last post is my findings from testing resistance to ground from the dead side of the fuse...Does that look ok?

Thanks again guys

[budm]

Re: Stinky Vizio VO370m No menu or picture.No voltage to T-con

The number on the fuse , I.E. is not standard that all the fuse manufactures use.
The letter on the fuse is not standard either.
BOURNS fuse 'N' is 1.60A.
LITTLEFUSE 'N' is 2A.

I would use 2A fuse fast-blo for testing for now, you can use axial lead fuse for testing.

[allsmith]

Re: Stinky Vizio VO370m No menu or picture.No voltage to T-con

Well hot diggity dog!! The fuse seems to have been the only problem...I rigged a 2amp fast blow on her and she works..I ran it for a hr or more...I'll get a order in for a fuse..I seen on here other posts about soldering the new fuse on top the old fuse..Is that ok to do in my case?

Thats a million guys.i owe you a cold beverage!...And if you ever need any advice on autobody and paint work just give me a holler!

[budm]

Re: Stinky Vizio VO370m No menu or picture.No voltage to T-con

'I seen on here other posts about soldering the new fuse on top the old fuse..Is that ok to do in my case?' Yes.