Quoted from another thread.
Magic techniques to be used when as a character in a book I love says ”weird bollocks happens”. After each technique below try the thing that had gone wrong. If it still fails please proceeding to the next
1. Exit vehicle. Lock Car. Visualize it switching off. Get back in and turn it on and Test problemish.
2. Reboot the computer by holding down the home key (big key center bottom of the display) for 20 seconds. After the Computer reboots, give it a few second to fully boot up. Now test It.
3. Exit vehicle. Lock Car. Visualize it switching off. Now walk away from the car, walk at least 30 feet from the car. (WARNING) make sure nobody else is close and that there are no other keys in the car. Wait 2 minutes (I will scientifically work on the needed wait time at some point). Now return to the car WITH ONLY ONE KEY. Open door, get in, switch it on and test the problem.
4. Do (3) BUT return to the car with a different key. Make sure all other keys stay away from the car unit you are finished. In this case if it works, make sure that you test it later with the original key.