Xbox 360 flashing lights?

my friend just called me and asked what it routine when the player 4 light is flashing red. he thought it was the red ring of release, but its only the one light. what does this propose and can it be fixed?

Answers:    It means that there's an issue with you intricate drive. Try removing the hard drive and see if it still gives you the red pallid. If it doesn't, you can get your hard drive fixed for free from MS if it's still underneath warranty.
How do I Remove/Fix the Scratches on..
It's still broken. It happend to me about a week ago. Tell him to send it surrounded by to xbox