20 Most Recent Sony 55 KDL55EX720 3D LCD TV Questions & Answers

You have to enter its service mode option to do a factory reset. Just visit these sites. I'm sure that you will get the details. https://homenol.blogspot.com/ https://elektrotricks.blogspot.com/ https://electrohelponline.blogspot.com/ If you wish to get some details; check the site linked here. Pull up older posts. Surf the site by type in the brand name of your TV, at its search box at the right column. View the sites by desktop computer or by Webview by mobile. Mobile view has no search box.

I simply followed these steps with a surge protectorpress the power button and hold upThen hold up with the power buttonthen let go of upand let go of powerworked with my kdl-55ex720

dear system board is defective you may change the complete system board 3x is DC alert fault thanks m Nasir

unplug everything. Plug one item in at a time and ensure you select the correct input. Test one item at a time to ensure it's actually the television causing the issue. Also, when you turn on the television with the power button on the side of the tv, press the menu button. if you have a menu it's a settings issue. lastly, if the power light is orange or red, and is blinking, this will indicate a problem with the television itself.

You have to contact the authorized service center for Sony to get a new panel.

Try changing the input device to something you are sure works. Switch off TV manually, switch off power, remove plug and retry after 48 hours. If problem persists, please refer it to a qualified service technician.

The set need a UPS with minimum 500W load capacity

I would try a new T-CON board first.

The problem in most of the case are: 1. Interference from a defective fluorescent lamp at your room sending signals to the infrared receiver of the TV. 2. Defective infrared receiver itself that sending noisy control signals to the CPU. 3. Defective manual control withes it has leakage. 4. Water damaged control switch PC board.

Do a reset to this TV, and then check. There are two methods to reset TVs. The first is simple to do; a Hard Reset. The other is somewhat skilled; is a Factory Reset (System Reset). To make it a hard reset, just unplug the TV from AC mains wall socket, and re-plug it back after 15 minutes or so. If you do this by overnight is better. This procedure will make it a hard reset. If you want to make it a system reset [Factory Reset]; you have to enter its service mode option, and select the factory reset option. If you wish to get some details; check the site linked here. Pull up older posts. http://electronicshelponline.blogspot.com/ Service mode entry, adjust and exit procedure to many popular brand TVs are given. Never forget to exit the service mode, after all adjustments have been done.

Those blinks [flashes] are fault indication (Error Codes). From the number of blinks occur at one time switch ON, you can get an idea about the faulty circuit section inside it. This will make repair easy. These are called blinking codes. Make sure about the exact number of blinking of the standby/power LED, by switching On & OFF the set, for at least two times. Count it carefully. If you wish to get some details, check the site linked here. It has details about blinking codes, and fault locating procedure, to many popular brand TVs and other devices. http://electro-medical.blogspot.com/ http://homenol.blogspot.com/ http://electronicshelponline.blogspot.com/

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....

Those blinks [flashes] are fault indication (Error Codes). From the number of blinks occur at one time switch ON, you can get an idea about the faulty circuit section inside it. This will make repair easy. These are called blinking codes. Make sure about the exact number of blinking of the standby/power LED, by switching On & OFF the set, for at least two times. Count it carefully. If you wish to get some details, check the site linked here. It has details about blinking codes, and fault locating procedure, to many popular brand TVs and other devices. http://electronicshelponline.blogspot.com/ If blinks continue without any pause, the main board is faulty. Search the site by type in the "brand name" to your device, in the "Search box at the top right of the display window of the Homepage" to get gathered related posts.

Fault to the main power supply regulator section. Either it will be a separate board, or the part of main board. Check and replace damaged component/s at its main power regulator [SMPS] section circuit. Contact any service technician. If you wish to get some details; check the site linked here. Pull up older posts. http://electro-medical.blogspot.com/ It will be best to replace the power supply regulator board as card basis rather than making "Surgery" to it; which usually will make loss for both money and time. Even though you can make it right, it will cost around an amount equal to the cost of a new board; including the cost of (spare parts + service charge) More to say, most of the spare parts to it will be difficult to get from open electronic spare part market. This is true to most of the flat panel TV power supply boards; irrespective of its brand and screen size.