General Hardware Failure
The Xbox 360 power button is a circle of four quarters, and if you see three flashing red lights appear, your console has a general hardware failure that is known as the "Red Ring of Death." The best remedy for dealing with this problem is contacting Xbox customer services.
Overheating
When the left side of the power button turns red, your Xbox is overheating. This will cause the console to crash, and while you may be able to restart your system, the error will continue until you address the issue. Remove objects that may cover the fans, allow enough room surrounding the console and place your Xbox 360 away from electrical devices.
Hardware Failure
If you see the bottom right section flashing, you have a hardware failure. This error will also be displayed on the screen with a message reading "System error, contact Xbox customer support."
First, disconnect all power cables and the hard drive, and leave the console for 30 seconds before reconnecting and turning your Xbox back on. If these methods fail, contact customer support.
AV Cable Error
When all four quarters flash red, you have an AV cable error. This may be due to an unplugged AV cable or a build up of dust in the socket. Unplug the cable and blow into the socket to remove the dust. If the problem continues, you may need a new AV cable.