Vizio vx42l reset button???

[lnfinlty]

Recently I was given a Vizio vx42l for free. When you plug it in, the Vizio light turns on. When you turn the tv on, the Vizio logo turns to white and the back lights turn on but no picture, no sound. Your unable to turn the TV off with the remote or the buttons on the side so I unplug it. Took off the back, and did not notice any bad caps or any indication that any of the boards are bad. I checked all fuses, one on the power board and 2 on the main board(?)

My question is, I've read about the reset button on the main board, but does it need to be plugged in when I press the reset button, or can I press the reset button after its been sitting unplugged for days?

I'm not an electrician. I work on computers so I have very minimal knowledge when it comes to flat panel tvs. I do not have any testing equipment but thought that if I read a little about this product, maybe I could get an idea on how much it'll cost to fix. If all I have to do is open up the back and press a reset button to fix this thing, I can do that. haha I would also pay $100 to replace the main board but if that doesn't work than I would be very angry. One of my friends just had his main board recapped and it put him back $200!! Thats insane. I'd rather learn how to do it myself for that much money!

[ecking767]

Re: Vizio vx42l reset button???

If all I have to do is open up the back and press a reset button to fix this thing, I can do that.

LOL That will be great !! if there was a reset button to fix all problem !!!

you will have to open up the TV and take picture of all boards, you will also need mutli-meter, a soldering iron, solder, and desoldering tool like: desoldering braid.

check you local radio shack for tools to get you started. not my 1st choice but you should be able to get started with out spending to much $$$

[daimoku]

Re: Vizio vx42l reset button???

Your problem is the main board. A SMD component needs to be replaced or you can replace the main board itself.

[lnfinlty]

Re: Vizio vx42l reset button???

LOL That will be great !! if there was a reset button to fix all problem !!!

Yeah tell me about it!! haha Here are a couple pictures of the main board and the power board. I think I'm going to buy a new main board. Someone I know just had his main board recapped for $200 and that only lasted less than a year and he ended up replacing the main board ($250 installed) last week by a tv repair man. I have found this main board on ebay for $100 shipped so I guess it wouldn't be too bad of an investment seeing how I did get this tv for free.

[daimoku]

Re: Vizio vx42l reset button???

Sounds good about the main board. Just make sure it's compatible with your panel. Usually these boards have the board number printed on the board and a white sticker with a bar code that has the board number. From the picture, it looks like you have a LG panel.

By the way, the pictures look good, but post them as attachments in the future. Some of our folks up north are on pay as you go Internet plans.

[PlainBill]

Re: Vizio vx42l reset button???

First of all, don't post pictures inline. It causes problems for people on a slow connection (dialup) and annoys the rest of us. Use 'Manage Attachments' below the text entry area.

If you can solder (or know someone who can), it might be possible to repair this board for much less than $100. This appears to be one of the boards that has a common fault.

Looking at the picture of the main board, notice the large connector at the top. That carries the signal to the LCD panel. There is a mounting screw to the right of that connector. About two inches down and slightly to the left of the mounting screw is U33, a LDO regulator. That has been a failure point on many Vizio TVs. It will be necessary to measure the voltages on it to confirm that is bad. If it is, a replacement regulator will cost under $5.00, shipping will be about $2.50.

PlainBill

[lnfinlty]

Re: Vizio vx42l reset button???

Oops, sorry guys didn't know about the pictures.. Definitely will remember that for next time.

I don't feel comfortable with soldering myself. I might call a few TV repair shops and get quotes. I know of one person that can solder and he wanted me to ask,

What values am I looking for when testing the U33 LDO regulator?

[retiredcaps]

Re: Vizio vx42l reset button???

What values am I looking for when testing the U33 LDO regulator?

PlainBill just wrote an excellent procedure (just yesterday) at

https://www.badcaps.net/forum/showpo...1&postcount=23

And yes, I'm one of those Canadians that has an ISP that has cap/usage plans.

[daimoku]

Re: Vizio vx42l reset button???

What values am I looking for when testing the U33 LDO regulator?

It should be 3.3V, but you will likely get around 2V if it's bad.

[lnfinlty]

Re: Vizio vx42l reset button???

Awesome! Thanks a million guys, I really appreciate the help. I've made plans for a friend to come over with a multi-meter to check the LDO regulator. I'll repost my results.

[lnfinlty]

Re: Vizio vx42l reset button???

So I finally had the time to test the U33 chip and it doesn't give a reading at all. Any suggestions on where I can order a replacement?

[Dgtech]

Re: Vizio vx42l reset button???

Before you run off and order parts, take a few minutes to confirm a few resistance readings. I'm guessing this is an LCD TV. If this is a plasma, ignore the rest of this post.

Out of all of the glorious pictures above, you never showed any pictures of the inverter boards, master or slave. Those inverters are notorious for failing driver chips. There is a small procedure I wrote up in the thread below for checking this board out.

https://www.badcaps.net/forum/showth...974#post129974

Even if the backlight is working, this board may be about to fail completely.

[gtrplayr1976]

Re: Vizio vx42l reset button???

I know this is an old post , but I have a set with the same issue. The U33 LDO is bad. I just need to know where to find a replacement ,and is this a fixed ,or adjustable regulator. I have not found this manufacturer at Mouser, or Digikey.
Part is marked AMC1117 F07131.

Thanks, Tom

[PlainBill]

Re: Vizio vx42l reset button???

I know this is an old post , but I have a set with the same issue. The U33 LDO is bad. I just need to know where to find a replacement ,and is this a fixed ,or adjustable regulator. I have not found this manufacturer at Mouser, or Digikey.
Part is marked AMC1117 F07131.

Thanks, Tom

Don't double post. When you post to an old thread it moves to the top of the list. Many of us scan all threads with new posts every time we come to the site. Double posting tends to annoy us - it's like a small dog constantly yapping to get attention.

The 1117 type regulators are available from a number of manufacturers. The manufacturer will had their own two or three letter prefix - National Semiconductor sells them as LM1117, Texas Instruments as TLV1117, etc.

PlainBill

[gtrplayr1976]

Re: Vizio vx42l reset button???

Don't double post. When you post to an old thread it moves to the top of the list. Many of us scan all threads with new posts every time we come to the site. Double posting tends to annoy us - it's like a small dog constantly yapping to get attention.

The 1117 type regulators are available from a number of manufacturers. The manufacturer will had their own two or three letter prefix - National Semiconductor sells them as LM1117, Texas Instruments as TLV1117, etc.

PlainBill

Sorry , didn't mean to annoy anyone ,but if someone had answered Infinitys question at the end of the post I wouldn't have posted at all. I was going to delete it , but didn't see a way to do that on this site. I DO appreciate the help ,but without the smartass comments.