Q: Yesterday the radio or display in my 2015 Chevy Cruze wouldn't come on, today both worked but car wouldn't start

The most common possibility is the battery is faulty. As the voltage decays, due to the battery being faulty, the vehicle enters the "saver" mode that you are seeing. The first thing to do is load test the battery. If the battery fails the test, or even passes but the pass is marginal, replace the battery. If the battery happens to be OK on the load test, you will need a no start diagnostic as obviously there is some sort of electrical problem preventing the car from starting. In both scenarios, once the car is running, charging system output should be tested and a quick check for excess current draw (aka, "parasitic power draw") would not be a bad idea in your circumstances (your car is new; the original battery should still be functional). All of the required diagnostic steps necessary to getting your car running properly again can be performed if you request a no start diagnostic. If you have further questions or concerns, do not hesitate to re-contact YourMechanic as we are always here to help you.