Macbook Pro Solid Sleep Indicator Light

Just recently I have noticed that my Macbook Pro will not sleep. When the lid is shut the sleep indicator light stays solid instead of pulsing as it should and used to. The light stays solid when but into sleep mode via the apple menu in the top left. Wake for network access and bluetooth devices is currently disabled. I have restarted my computer multiple times and left it off over night to no change. I have attempted reseting the SMC and the PRAM and still have the problem. When the computer is supposed to be sleeping you can clearly hear the fan running. It appears the moniter is sleeping as it should but the computer itself refuses to sleep. As well, I am running OSX Lion with all my software updated and no third party applications. Currently I am shutting my Macbook down whenever I am not using it. How can I get my Macbook Pro to go to sleep?