How to Determine the Xbox 360 Secondary Error Code
If you have the 3 red lights or "RROD" or 1 red light on your Xbox 360, follow these steps to determine your Secondary Error Code:
Here is how to convert the lights into a code:
1 light = 1
2 lights = 2
3 lights = 3
4 lights = 0
So, for example if you get 4, 1, 1, 4, your error code is 0110.
** Please Note: If you have error code 0003, do not send it in. This is usually a power problem, so try replacing the power brick first. If a system in sent in with Error Code 0003 it will be sent back.