ok.. když nesvítí kruh ale jen prostředek tak je nejspíš problém s napájecím zdrojem..Red power supply light: Try the next solution. Turn off the console. Disconnect the power cord from the back of your console. Unplug the power cord from the electrical outlet and from the power supply unit. Plug the power cord back into the console, reconnect the power cord to the power supply, and then plug the power cord into a different electrical outlet. Make sure the power supply is positioned so that it gets good ventilation. Turn on the console and check the power supply light.If the light on your power supply is still red, your power supply needs to be replaced. Order a new Xbox 360 power supply from Device service and repair. Console registration is required to replace a power supply under warranty (the power supply warranty is the same as your console warranty).
