Once in a while I turn the key and all dashboard lights come on, but the car won't start, it's completely dead. So then I jump it and it starts. This problem is off and on. Sometimes it starts right up and other times I turn the key and nothing happens. The battery, alternator, and starter all tested good at the service station. Could it be a loose wire, connection somewhere? or could it be something with the key and the ignition? Someone also mentioned a problem with the ignition box.