Re: Vizio P502ui-B1E power light turns on, but no picture

I should share my experience as well.

I'm not nearly skilled enough to do a proper reflow, and lack the necessary tools anyway, so I simply used a heatgun to 'cook' the mainboard every time it stopped working (see my OP above for how the TV behaves in that state). I laid the mainboard flat and used a cheap Chicago Electric #69343 heatgun, at the High,970F setting, aimed at the large heatsink right above the north BGA chip, about 1cm away for 60 seconds (note that this is probably too much heat if you have a...

Re: Vizio P502ui-B1E power light turns on, but no picture

Thanks! You nailed it!

Guess I'm gonna have to cook the CPU every now and then...

Re: Vizio P502ui-B1E power light turns on, but no picture

Thank you for your reply, this didn't work unfortunately. Also, this TV does not have a physical channel up button - it only has a power button on the back. So when following your directions, I tried keeping the physical button power pressed as I plugged it into the wall socket, then tried keeping the channel up button pressed on the remote as I plugged it in, then a combination of the two. No luck.

Any other ideas? Thanks in advance.

Re: Universal Programmer Recommendation

So I tried a thing today...
I designed and 3D-printed a little eeprom chip reader and hooked it up to the SPI pins on a Raspberry PI. And... it works! Both onboard (with an external 3.3v PSU) and offboard. Best part is - it supports a huge number of chips (uses the Linux flashrom util), and you can look at the bit-banging live with Piscope. All for $0!

Here are my schematics, for anyone who wants to repeat my little experiment....

Hey guys,
I have a Vizio P502ui-B1E with no display activity at all with the power light on. It broke in a very specific way, and now exhibits strange behavior when turned on (slow response to power off command, restarts every 90 sec, more below), so I'm hoping that someone with experience working on this TV can point me in the right direction.

I already tried the 2 most common fixes with no luck:
- Replacing the T-Con board.
- Re-flashing the firmware on the U202 chip (from here: [url]https://www.badcaps.net/forum/showthread.php?p=840012[/url])

...

Re: New Members - please post your introductions here

Greetings from NYC!

I've got a broken Vizio TV I need to make a thread about...