Vizio GV42LHDTV No Digital Channels

[nomoresonys]

Re: Vizio GV42LHDTV No Digital Channels

Well here's some more crap to try: https://www.fixya.com/support/t23906...ed_getting_all

[newbie48]

Re: Vizio GV42LHDTV No Digital Channels

I realize this is an old posting and no one will probably see this but hey nothing ventured nothing gained. I have a 2007 Vizio GV42L HDTV too which I love with same tuner issue ie won't scan for digital, just the analog. I tried all the suggested fixes; the last one being the take TV apart (a challenge) and wiggle the wee pot as suggested by loudhvx. No change. Tried it again. Still nothing. I give up. I think I am going to try the external tuner solution that FriedFarmer I think talked about having as they are cheap ($25-$30...much cheaper than taking TV to repair shop) and give you features not included with TV like DVR functionality.

[Loudhvx]

Re: Vizio GV42LHDTV No Digital Channels

The cans with the dark adjustment screws are actually coils with a ferrite bead in it (no physical contact) and as you adjust the dark screw or ferrite bead the number of Micro-Henries or Milli-Henries change in a tuning circuit. DON'T adjust these.

Yes, I mentioned that in the post before yours. Maybe you didn't see it. But thanks for the confirmation.

[Loudhvx]

Re: Vizio GV42LHDTV No Digital Channels

I can now post photos, so here they are. I also included photos of the regulator that "102mm" replaced in his video.

Cover over main board.


Main board exposed.


RF enclosure.


RF enclosure with lid popped off.
Don't adjust the inductor can (left of pot in photo). Only the tiny potentiometer.


Closeup of potentiometer (center of photo).
Don't adjust inductor (left side of photo).


Main board showing regulator marked AMC 1117 F0632J


Regulator marked AMC 1117 F0632J

[Andrew F. Ali]

Re: Vizio GV42LHDTV No Digital Channels

The cans with the dark adjustment screws are actually coils with a ferrite bead in it (no physical contact) and as you adjust the dark screw or ferrite bead the number of Micro-Henries or Milli-Henries change in a tuning circuit. DON'T adjust these.

[Loudhvx]

Re: Vizio GV42LHDTV No Digital Channels

Since I can't put up photos yet, I should mention, the potentiometer I exercised was a small metallic one, which appears like a small rivet or small screw-head. I don't think it would be recommended to exercise the variable inductors. They look like rectangular cans with a dark adjustment screw inside the middle. Those screws don't make direct electrical contact, so there would be no benefit to rotating those.

[Loudhvx]

Re: Vizio GV42LHDTV No Digital Channels

I wanted to post several photos, but I guess I don't have permission to access my profile page yet.

[Loudhvx]

Re: Vizio GV42LHDTV No Digital Channels

Hi, I realize this is a really old thread, but I thought I might be able to add some info to it.

First, I want to thank everyone else who posted here.

I am working on a Vizio VX37L. The tuner portion of the main board looks pretty much like the one on the GV42L. And I have the same problem. The autodetect completes the analog channel search, but does not even begin to search the digital channels. The progress bar does not turn yellow at all.

However, my problem is more intermittent in that it did work one time, then found about 70 channels. But later that day the TV only had a blue screen and no channels worked except the one analog channel. After that the autodetect never worked again on the digital search.

I tried the various suggestions posted here, but I don't have a remote. It seemed like I could do most everything I needed with the buttons on the side of the unit. The "unchecking" the individual channels could not be done. The checks were grayed out.

Based on 102mm's post, above, and the excellent video, I opened the unit and checked the 1.25v regulator. It was rock solid.

So then, as a last resort, I popped open the RF enclosure. Inside was what I assume is a really tiny potentiometer. I rotated it back and forth multiple times, probably like 20 times, vigorously. I made sure to note what position it was in, and put it back to that position.

This seemed to fix the problem, but I can't say for sure it wasn't something else I may have touched. The digital channel search progress bar immediately had a tiny portion turn yellow, and after about 2 or 3 minutes it found 70 channels. I reassembled the TV and after 24 hours, it is still working.

[102mm]

Re: Vizio GV42LHDTV No Digital Channels

https://www.youtube.com/watch?v=qC9FEZ78-qM

[SteveH]

Re: Vizio GV42LHDTV No Digital Channels

It did not work for me and after having many of these sets to repair I have never found a solution.

[Myers]

Re: Vizio GV42LHDTV No Digital Channels

Hi everyone. Because of Cox Cable and the "Mini Box" I thought it was time to cut the cable. I also have a Vizio and had the same problem as people posted but I figured it out. In the settings before you do your "Auto Scan" go to "Channel Skip" and de-select (remove the check) from EVERY channel. After you do this do an Auto Scan and enjoy your new digital channels! (Make sure you attached your HD antenna) For some reason the Vizio tuner will not pick up both analogue and digital channels in the scan and no where in the manual or anywhere else does it tell you to do this. I did how ever get 1 analogue channel after I de selected all of them. Go figure.

Anyways, if anyone is still having this issue, I hope this helps.

Can anyone confirm this? I have had a bunch of vizio tv's in here in the past and never really fingered it out?

[malcolmar]

Re: Vizio GV42LHDTV No Digital Channels

Hi everyone. Because of Cox Cable and the "Mini Box" I thought it was time to cut the cable. I also have a Vizio and had the same problem as people posted but I figured it out. In the settings before you do your "Auto Scan" go to "Channel Skip" and de-select (remove the check) from EVERY channel. After you do this do an Auto Scan and enjoy your new digital channels! (Make sure you attached your HD antenna) For some reason the Vizio tuner will not pick up both analogue and digital channels in the scan and no where in the manual or anywhere else does it tell you to do this. I did how ever get 1 analogue channel after I de selected all of them. Go figure.

Anyways, if anyone is still having this issue, I hope this helps.

[rottencorpse]

Re: Vizio GV42LHDTV No Digital Channels

Hi - Wanted to provide my experience with this issue as it may help others.

I have the same Vizio TV GV42L and after cutting the cord and installing an OTA antenna I needed to get the TV to recognize digital channels.

Unfortunately I ran into the same issue others experienced-- after scanning the analog channels it would stop. I tried resetting and all the other typical troubleshooting things others have mentioned. No luck.

I called Vizio support and they suggested a new board.

Then I finally found the original remote and went through the same reset procedures and scan using the remote (as opposed to the menu on the TV).

It worked. I hope this helps someone else!

How do you do a scan with only the remote?

[caribbean]

Re: Vizio GV42LHDTV No Digital Channels

Hi all, I'm new at this forum and this is my first post.
I got a GV47L for repair with a power supply issue. After repairing this I detected the same "digital" problem. The demodulator is definitely not the reason. IF out shows changing patterns during scan. Solution is to load up new firmware. Does someone know how to do it?

Thx

Rafael

[cliff_hootarski]

Re: Vizio GV42LHDTV No Digital Channels

Did you check the DU4 voltage regulator? I think that was the problem with the board on the TV I mentioned earlier in this thread.

[Berkonet]

Re: Vizio GV42LHDTV No Digital Channels

Hi - Wanted to provide my experience with this issue as it may help others.

I have the same Vizio TV GV42L and after cutting the cord and installing an OTA antenna I needed to get the TV to recognize digital channels.

Unfortunately I ran into the same issue others experienced-- after scanning the analog channels it would stop. I tried resetting and all the other typical troubleshooting things others have mentioned. No luck.

I called Vizio support and they suggested a new board.

Then I finally found the original remote and went through the same reset procedures and scan using the remote (as opposed to the menu on the TV).

It worked. I hope this helps someone else!

[cliff_hootarski]

Re: Vizio GV42LHDTV No Digital Channels

I had the big brother of your set (GV47L) that did the exact same thing. Figured it needed the main board replaced so I sold it at a steep discount.
Mainboards for the 47" on Ebay run about $115 (US Dollars) and up.

[Friedfarmer]

Re: Vizio GV42LHDTV No Digital Channels

Just to let you know, I had a problem like this with the same type of vizio set and I didnt find a way to fix it so I sold it. So... it's not just you.

Check below for the thread that I started with that TV. You'll find that someone else had the sampe problem.

https://www.badcaps.net/forum/showth...ighlight=GV42L

Yeah, It's definitely a strange one. I saw your posts before when I first starting researching this problem. Was wishing that you had solved it. I'm going to look further into the power supply, there may be some ripple voltage causing the problem.

[Dgtech]

Re: Vizio GV42LHDTV No Digital Channels

Just to let you know, I had a problem like this with the same type of vizio set and I didnt find a way to fix it so I sold it. So... it's not just you.

Check below for the thread that I started with that TV. You'll find that someone else had the sampe problem.

https://www.badcaps.net/forum/showth...ighlight=GV42L

[ecking767]

Re: Vizio GV42LHDTV No Digital Channels

It would be very unlikely that 2 main boards would have something like a bad digital tuner.

Its not a bad tuner, the scanning of the digital channels never get store in to memory or get completed. The scanning of channels stay at 0% for the digital channels. Its not a tuner problem.
its possible to have two bad board. its happen to me when I made a purchase of a T-CON from shopjimmy .