Hyundai sonata intermittent no start

My daughter’s 2005 Hyundai Sonata continues to strand her periodically (12 times in the past 18 months). Sometimes weather seems to affect it - warm/hot not good. It will not start after being driven until warm/hot (esp. with air cond. going) and left to sit for a relatively short amount of time. Lights and bells sound, but absolutely no action from engine. If left to sit a couple of hours, it starts as if nothing had happened. Hyundai isn’t cooperative, as it never acts up when in shop. The problem started while still under warranty, but it is now over 6K and warranty is off. Anyone out there ever have similar problem? Any advice?

Hyundae just does not want to bother. Technically, since it was reported while still under warranty, they’re obligated to fix it under warranty.

But if it were my daughter I’d take it straight to a reputable independantly owned and operated shop. The heck with Hyundae, there’s a daughter-safety issue at stake.

This problem is diagnosable. This should have stored fault codes in the ECU. These can be read by the willing. Beyond that, various ignition components that commonly cause these symptoms can be tested for susceptability to heat failure.