I have a 2011 Sony bravia LCD TV model kdl 40ex621....I hit power button and red led turns green then switches right back to red and blinks 4 times, I need to know what board to replace. Thank you!!

SOURCE: Sony Bravia KDL-40V300 won't turn on.

Unfortunately 5 blinks is a LCD panel error. The only way to fix it is to replace the whole LCD panel. This is the most expensive part in the TV.
part number: 1-802-488-12
List price: $1336.32
Core charge: 1790.00
You could try to replace it yourself but would need to take the whole TV apart by first taking off the back cover, then removing all the boards in order to get to the panel before putting it back together but I would just recommend buying a new TV as the price of the repair exceeds the price of a new TV of the same size.

SOURCE: I have a SONY BRAVIA

If it does not turn on or turns on and then right back off it is most likely the power board.

I had a similar problem with my 42 in Philips LCD HDTV.

Here was the problem. My Power Supply Board had several bad capacitors. I opened my TV (warranty was expired of course) and found four bulged capacitors on the PSB. Many major electronics companies Philips/Magnavox, Sony, Panasonic, and others were sold capacitors that failed in 2-5 years instead of 10-20. The capacitors fail prematurely due to a lack of preservatives. Unfortunately, they were installed in all sorts of devices and cause a wide range of failure problems.

Here are some options for you.

1. Have it fixed by a professional $$$$$$$??????? (Is it under warranty?)

Remember, TVs CONTAIN HIGH VOLTAGE AND CAN KILL YOU! Do this at your own risk.

2. Open your TV and find PSB. (The board that the power cord plugs into) Check for faulty caps. If you find some (bulged or leaking) bad caps replace the entire board. The entire board costs around $250 right now because they are in high demand right now. They can be found online. I would definitely shop around though.

3. Remove and then replace individual faulty caps. This takes some soldering skill.

Caps are inexpensive and if you can take care of it yourself it will save you hundreds.

This may be your problem. If you determine that it might be.

I have a Tip/How TO tutorial on this site that may also help. It gives step by step instructions for replacing caps on PSB #715t2432-2. If this is your board you are in luck. Here is the Link: Fixing the Philips Turns/shuts off on its own problem. I'm working on uploading pictures to help guide people though the process as well. Let me know if I can do anything to help.

Hope this helps and if it does please rate it accordingly. Good luck.

SOURCE: sony bravia l42" LCD TV. No power. Green light on

7 blinks in the this series(KLV) means there is a short in the power supply board. The easiest way to fix this would be to swap out the board. I can find you a replacement if you want to try fixing this yourself.

Sai.

SOURCE: Problem with Sony Bravia 46" TV (Model

blow out fan in mother board tower mother is over heating and not geting enough of air leting the mane chips over heating makes computer stop so it doesnt catch fire.

SOURCE: Sony KDL-40S4100 Bravia LCD will turn on for like

B+ over current protection (OCP), unit goes to the standby mode then displays the 2 blink fault. Could be a short in the power supply of any of the circuits.