Vizio E422VLE screen problems when cold started. Works fine after 20 minutes.

[SdlewisSr]

Re: Vizio E422VLE screen problems when cold started. Works fine after 20 minutes.

Before I used the hair dryer on the tab I used a 5mm nozzle and 2mm nozzle (see attached image) on my SMD rework station to heat the PCB. I heated each SMD on the PCB. It was when I used the 5mm nozzle on the tab that I discovered that heating only the tab fixed the problem. I took my time holding the 2mm over each component on the PCB with no effect. I was not heating the PCB when I used the 5mm on the tab. When I heated the PCB end of the tab, there was no effect. Only when I heated the panel side of the tab did I discover that the tab was the issue. I used a hair dryer in the video only because it was easier. I tried pressing lightly on the tab to see if maybe using a shim would work but it had no effect. I will try to find the thread that you suggested.
Thanks

[vinceroger69]

Re: Vizio E422VLE screen problems when cold started. Works fine after 20 minutes.

thanks for the update i have included the link for the tab bond fix in my last post there are also some guides on youtube basically it involves putting a shim over the tabs so when the sets assembled it puts pressure on the faulty tab bond, has the ribbon cable between the pcb and lcd panel have a small ic on? cof (chip on flex) as that may have bad solder etc hence working whilst heated.

[dick_barton]

Re: Vizio E422VLE screen problems when cold started. Works fine after 20 minutes.

Take your time and you should be successful with the fix. As Vinceroger69 says there are some good Youtube videos to guide you.

[SdlewisSr]

Re: Vizio E422VLE screen problems when cold started. Works fine after 20 minutes.

Thanks. I will try. However, it may be a couple of days before I can get back to the TV.
I really appreciate your help.
Have a blessed day.

[SdlewisSr]

Re: Vizio E422VLE screen problems when cold started. Works fine after 20 minutes.

I have tried pressure on the tab/lcd glass bond and it has no effect. Pressing on the flexible part of the tab itself has no effect either. Therefore I assume a shim would not help. I have included some photos of the tab. There appears to be an IC on the tab (cof) as vinceroger69 mentioned. Since my last post, I reassembled the TV to determine if I could just use the TV as is by heating the corner with a hair dryer before turning it on. Fully assembled I can heat the LCD glass in the corner near the tab for 10 secs and it works when I power it up.
Have a blessed day

[vinceroger69]

Re: Vizio E422VLE screen problems when cold started. Works fine after 20 minutes.

certainly a odd fault as budm has fixed this fault himself with shims maybe he will have a idea if it will work on your set

[SdlewisSr]

Re: Vizio E422VLE screen problems when cold started. Works fine after 20 minutes.

If I am reading the budm thread correctly, it seems like the opposite problem to the one I have. It appears that budm was trying to transfer heat away from the tab, but I need heat to go to the tab.
I can live with using a hair dryer for a few seconds before I turn the TV on. Normally, when I turn a TV on, it will be on a few hours anyway. I just would like to understand what is exactly happening for future reference.

[dick_barton]

Re: Vizio E422VLE screen problems when cold started. Works fine after 20 minutes.

If putting light pressure on panel / pcb ends of the ribbon is not doing it, then try light pressure on the IC (COF) in the middle of the flexible tab.

Wherever you are warming up with the hair dryer is expanding the contacts due to heat resulting in making a good connection.

[SdlewisSr]

Re: Vizio E422VLE screen problems when cold started. Works fine after 20 minutes.

I tried pressure on the flexible part of the tab, including right on the COF with no effect.