Engine was running fine, then it did not want to start later that day?

check fuse #12 which supplies power to the park/neutral safety relay if it is good then you could have a problem with the park/neutral relay (should be in the underhood fuse box), the neutral safety switch (on the transmission), the ignition switch, of any of the wiring or connections in between the ignition switch and the starter. Other than replacing parts - you can swap the relay with another relay in the fuse box for quick check, if it works replace the relay - you will need a wiring diagram, and understanding of how to test electrical circuits and a volt meter. Even though the lights come on in the dash, sometimes an ignition switch wears out the contacts to the starter circuit. Also, if the vehicles is equipped with a factory anti-theft system or after market alarm with a starter disable feature, both have additional components which can prevent the starter for engaging. Robert Grove www.wego2umobilemechanic.com 949-288-3506