Re: Vizio 40” V405-H19 has backlight, no display
might have gotten a bad mainboard from sj, maybe send it back and have them send you another.
might have gotten a bad mainboard from sj, maybe send it back and have them send you another.
-
-
Re: Vizio 40” V405-H19 has backlight, no display
Good lord. Here I was complaining about tcons being built into main boards but this guy's got a tcon built into the panel board! Vizio is one step ahead in the cost cutting / making it hard to fix gameDon't fear the repair...Comment
-
Re: Vizio 40” V405-H19 has backlight, no display
VGH and VGL are generated on t-con.I assume no responsibility for any stupid suggestions I might post.Comment
-
Re: Vizio 40” V405-H19 has backlight, no display
As far as voltages the main only supplies 12v. Required panel voltages are generated by t-conI assume no responsibility for any stupid suggestions I might post.Comment
-
Re: Vizio 40” V405-H19 has backlight, no display
The main board has to give the tcon some other small voltage signals for the picture data...most of the pins on the connector going to the tcon are those, right? And a few are for the 12v. I guess I should try lookup a pinout to see for sure what the mb sends.
Also while they're busy integrating boards that they shouldnt be, who's to say they haven't put half of the "tcon" on the mainboard and the other half on the panel boards??Last edited by triplefour; 07-28-2022, 09:41 PM.Don't fear the repair...Comment
-
Re: Vizio 40” V405-H19 has backlight, no display
The main supplies 12v, data signals and some other information. The t-con generates the required panel voltages and timing signals to run the panel. The chip around your vgh and vgl test point is probably the one generating those voltages. So you either have a short or bad ic.I assume no responsibility for any stupid suggestions I might post.Comment
-
Re: Vizio 40” V405-H19 has backlight, no display
ok, if tcon is on the panel not mainboard, might be the dc to dc converter ic.Comment
-
Re: Vizio 40” V405-H19 has backlight, no display
Wow, that was a lot of information and good Q/A. Is there a way to test the IC? I suppose I would need a pin out diagram and what the voltages should be.Comment
-
Re: Vizio 40” V405-H19 has backlight, no display
You could check those test points for shorts. You could cut the traces and check the voltage. Check the caps around the ic. Check for 12v to the ic.I assume no responsibility for any stupid suggestions I might post.Comment
-
Re: Vizio 40” V405-H19 has backlight, no display
I don't know exactly how they work either but I think you want to look for 12v going in and 3.3v coming out on one of the pins.Comment
-
Re: Vizio 40” V405-H19 has backlight, no display
Which of the 3 ICs do I check?
Attached Filesif you find these attachements useful please consider making a small donation to the site
Comment
-
-
Re: Vizio 40” V405-H19 has backlight, no display
Looks like right one.I assume no responsibility for any stupid suggestions I might post.Comment
-
Re: Vizio 40” V405-H19 has backlight, no display
There will be different voltages on each on the coils, so it's the middle and right but identify the markings to be sure.Comment
-
Re: Vizio 40” V405-H19 has backlight, no display
The only two voltages I found close to what you were asking was pin 1 starting from the top left above the “I” in “INX” which measured at 4.970V and pin 3 above the “N” at 12.63V. I tried looking up the chip but couldn't find anything specific.Attached Filesif you find these attachements useful please consider making a small donation to the site
Comment
-
-
Re: Vizio 40” V405-H19 has backlight, no display
I included the above drawing. Hopefully you can make sense of my scribble.
I still need to draw a diagram of the other chip but I measured 12.63 volts as well as 5v. There were other voltages that measured between .600 and 1.5 volts.Attached Filesif you find these attachements useful please consider making a small donation to the site
Comment
-
-
Re: Vizio 40” V405-H19 has backlight, no display
I can't seem to find a datasheet on it either.Comment
-
Re: Vizio 40” V405-H19 has backlight, no display
Nice...tcon integrated into panel boards and secret ICs... they really don't want you to fix these
If that ic is bad and there's no way to buy a new one then your only chance would be to take it from another TV but most ebay sellers don't tear off and sell the panel boards. Now that the tcon chips are there, maybe they should. I've been saving all my panel boards even tho they don't have tcon on them.
Last edited by triplefour; 08-02-2022, 09:44 PM.Don't fear the repair...Comment
-
Vizio e601i-A3 - Has Sound and Display, But No Backlight - Bad Power Supply Board or Bad LED Bulbs ?I was given this TV from my great uncle. He said it just wouldn't turn on one day out of nowhere, replaced the TV, and gave it to me to possibly fix and use for myself.
Upon bringing it home and plugging it up, it showed a standby light.
I powered it on and without a flashlight, the display showed the "V" but the lighting is very dim, but visible.
The screen seems to blackout and stay black, but with a flashlight I can see the display.
With my Playstation 4 connected via HDMI, and running a game I can hear sound.
Assuming... -
this tv is throwing me for a loop. do samsung tvs no longer have the backlight self test feature built into the power supply?
i tested the backlight with my LED tester and it lights up both strips. one of them reads 100v and the other reads 63.7v.
unplugged mainboard from power supply but left backlight plugged in, and then plugged psu wall power in. expected to see backlights light up but see nothing.
according to how ive diagnosed in the past, this would almost always be a bad power supply. replacement power supply was cheap like 20$ from ebay. but still i get not even... -
Hi, I have a Samsung UE50TU with:
- sound and backlight, but no picture
- when it arrived, it had a picture for a few seconds
- it keeps rebooting
- without ribbon cable between the two panel boards, it does not reboot but I have no picture
- without cable between mainboard and lcd panel, it does not reboot (but obviously i have no picture)
- when i try a tape fix, its keeps rebooting, unless I tape off pin 1 (the innermost pin). In that case it does not reboot but I have no picture.
- without cable between mainboard and lcd panel and with a jumpered... -
Hello everyone,
Ive got a UE60KU6079 on the workbench that is giving me some headaches trying to troubleshoot.
The previous owner stated that there had been white dots on the screen which from the description sounded like some lenses fell of the backlight LEDs.
He had opened the TV from the back, trying to get to the backlight, supposedly gave up, reassebled everything and gave the TV to me.
I expected the worst like ripped COF cables or a cracked panel but could not find anything like that yet.
Anyway I still fully expect that there has been something seriously damaged... -
vizio e650i-a2 (LWJAOZBP Serial) led backlight flashes then turns off, has video (via flashlight) and audio.
panel: au optronics T650HVN05.4
72 led total on 12 strips, 6 led per strip wired in three groups of 24 (led driver board has three anode and three cathode pins)
link to datasheet: https://datasheetspdf.com/pdf-file/8.../T650HVN05.4/1
Vizio 56.04219.641G (liteon PA-3231-01WN-LF) Power Supply Unit
https://www.shopjimmy.com/vizio-56-0...-power-supply/
Vizio 55.75J01.001G (91.75J10.004G) Main Board...
Comment