My proscan tv 39 inch PLDED3992A WILL NOT POWER ON AT ALL IS THERE A RESET BUTTON.

The Proscan PLED5544U is a 55-inch LED TV. While it doesn't have a physical reset button, there are a few ways you can reset it:

1. Unplug the TV: Unplugging the TV from the power outlet for a few minutes can help reset it. This allows any residual power to dissipate and can clear any minor software glitches.
2. Use the remote control: Press and hold the power button on the remote control for at least 10 seconds. This can sometimes reset the TV.
3. Use the menu: If you can access the TV's menu, you can try resetting it through the settings. Go to the "Settings" menu, then "System" or "General" settings. Look for an option to reset the TV to its factory settings.

If none of these steps work or if you're experiencing other issues with your TV, it may be best to contact the manufacturer or a qualified technician for assistance.

Flickering can be adjusted. To some rare cases, the SMPS [Power] board might need replacement. If you wish to get some details; visit the site linked here. Pull up older posts. http://electronicshelponline.blogspot.com/

No the TV has failed. most likely the main PCB has failed or is shorted. To repair this will be close to the cost of a new TV at current prices.

Back - light problem. Check and replace damaged component/s at its back-light inverter board, or replace this board as card basis. If you wish to get some details; check the site linked here. Surf the site with patience. Pull up older posts. It will be best to replace the inverter board as card basis.
http://electronicshelponline.blogspot.com/
To some model sets; especially LED back-lighted types; the back-light inverter circuit will be part of the main power supply board [SMPS]. In such cases, the power supply board might need replacement. To some models sets, the back-light inverter and SMPS section circuit will be integrated at its main board itself. If so; the main board should be replaced. To some models of sets, all these section circuit will be integrated at its main board. If this is the case, you have to replace the main board.

Bad card. Electro help

some televisions require a seperate audio feed from the HDMI cable to hook up audio. if you have the cables for this i would try that first. normally ends up having to go thru an AV connection

There's now way the ir files could get from Comcast into your remote. Without a upload. So yes.

Your problem is most likely in the main power supply or possibly in the sweep power supply. Without the know how and a service manual, you could turn a minor problem into a mojor headach.. LOL Play it safe and invest in a pro to assist you in this repair. The 'rough' ride might have loosen some connections.

power supply probably needs to be rebuilt, vertical IC some filters,probably a couple of transistors. best to have an experienced tech do it for you.

Just try to reset;

Resetting the TV
Some TVs have a reset button. If available and accessible, try using the reset buttons before using the steps below. Using the reset buttons can saved time.
1. Unplug the TV power cord from the power outlet for 3 - 4 hours.
2. Unplug any connected devices (DVD, Set-top boxes, etc...)
3. Press and hold the TV power button for five seconds.
4. Plug the TV power cord back into the power outlet and turn on the TV.
5. Open the on-screen menu to confirm that the TV is responding again.
6. Turn off the TV and reconnect the devices.
7. Turn on the TV.

hope this may help;

Regards,
VOTIT