assuming that the battery and the key fob is all good lock and unlock the car a couple of times with the key in the drivers door then turn on the ignition and push the lock/unlock buttons on your key fob up to 8 times then turn off the ignition and try to lock /unlock the car using the remote this procedure syncronizes the key remote to the car if the rolling code has been lost due to remote battery going flat
                 gtwannabe
                
 February 2009