SONY 3LCD 60 INCH WONT TURN ON

3 blinks is usually lamp door not closed properly (can mean door is warped from the heat also).

Three flashes is lamp cover/lamp position error, it means the lamp cover is not set right, or the lamp is not in the right position. There are two micro switches to detect the lamp position, and lamp cover. Please reset the lamp and the lamp cover (door).

U might just have a bad ballast. It generates the high voltage to fire up your bulb.

When I plug the LCD the LAMP/COVER flsh blinking red light

4 blinks is fan error. Just clean the fans near lamp compartment by a vacuum cleaner and check the fan connectors if they are attached securely.

I bought a new blub for it and the light still goes green then red.Anybody know?? mg

This mean the bulb is burt out. You need to replace it.

Here is where you can get them...
http://www.bluestar-online.com/XL5100_Sony_Replacement_LCDLamp_p/xl5100.htm?gclid=CLiB4d-Ls5gCFQ7aDAod5UYWlg

Green flashing is normal. Red flashes are error codes. Count the error flashes.

3x - Lamp cover position or cover detect switch bad.
4x - One or more fans failed RPM test
5x - Lamp power supply/ballast failure
6x - Thermal fuse failed (usually)

MINE DID THAT AND IT WAS THE THERMOSTAT FOR THE BULB

Possible themal sensor. Easy to bypass too!!! Check with authorized Sony repair facility.