What can cause the remote start to stop working on 2005 Chevrolet Malibu

Already replaced the batteries in the remote but it still does not trigger the remote start.

2 answers
my 2007 buick lacerne wont start car by remote
Have you another remote to try? I have before taken apart the remotes and cleaned the circuit board in remotes with circuit board cleaner you get in Radio Shack. Perhaps a better cleaner that is safe for electronics is for cleaning air flow meters available at auto parts stores CRC product # 05110