There are several methods to solve this problem. The easiest way to do this is by using a towel! This will only provide a temporary cure, your machine may stop working again after a few hours. My suggestion is to follow this method and then sell your machine on to a second hand shop then run!!

The three red light error code on earlier versions of X-Box 360 is very common. Microsoft were actually in denial for a long time about it. The problem arises due to weak soldering joints on the circuit board. By temporarily overheating the machine then letting it cool again suddenly, you will re-melt the weak solder joints and allow them to reform.

1. Take all the wires and attachments off your broken X-Box 360, leaving only the power supply attatched.
2. Get a large towel and wrap it fully around your machine and turn on the power.
3. leave it for about 15 minutes. Do not leave your machine unattended. setting a reminder on your phone is a wise move.
4. When you have done that, immediately place the X-Box in the fridge with the towel in place. Leave it again for about 15 minutes
5. You should now have a working machine.

I recommend that you try this method as a last resort. You do so at your own risk and it is entirely your sole responsibilty. This technique is not endorsed by microsoft in any way whatsoever and is not an official method of X-Box 360 repair. All attempts should be made with total concentration, specifically whilst not under the influence of alcohol or drugs. Anyone under the age of 16 should consult their parents before fixing the X-box 360 using a towel. I hope you succed in your attempts.