Sounds like you may have left something turned on and run the battery down. Try recharging it and then see if it starts. I think it will.
it sounds like a dead battery recharge and try again
When you hear a clicking noise is most likely a battery problem however you stated that the battery was replaced so i suggest you check the condition of your cables look for rust or corrosion etc.
If it is a rapid clicking, the battery has failed.
Have noticed the same thing on two 2005 MCS. Does not appear to be a problem; they just make that noise.
How to Start Your Own Country - 2005 is rated/received certificates of: UK:15
How to Start Your Own Country was created on 2005-08-03.
How to Start Your Own Country ended on 2005-09-06.
My car is doing that too. It was fine one minute and the next minute it won't start. All I'm getting is this clicking noise from the Fuse/Relay box under the hood. Is this what your car is doing?
Noise - 2005 II was released on: USA: 11 November 2005
Try this link. I have a 2004 Envoy and mine is doing it. http://forums.trailvoy.com/showthread.php?t=48777
Mine sounded like a large lizzard was in the airbag compartment and it's tail was hitting the sides. This had something to do with the AC motor so I was told by Pontiac service. I took it in today for the same reason.
Bar Noise - 2005 was released on: USA: 10 September 2005 (Oxford Film Festival)