If my Jeep has been sitting for awhile, it doesn't always start right away. I have to try several times for it to finally turn over. It doesn't make any engine noise as if it were trying to turn over, just a single click when it goes past 'ON' to 'Start'. It seems like the longer it has sat or the colder the weather is, the more trouble I have with it. If I drive it somewhere and get right back in it, then it starts just fine - my guess is because its already warmed up. I don't believe its the battery because the instrument and control panel lights come on and the radio too. Plus I had the battery tested and they said it was fine, and the terminal connections were tight... What else could it be?