Q: Car turned off completely during highway driving

In order for an engine to continue running, it must have three things. These things are compression, fuel, and ignition. If one of those three things goes away, the engine will no longer run.

I would recommend checking your alternator first. Although the alternator is not directly a part of the fuel or ignition systems, an alternator failure could cause these systems to malfunction.

The alternator is what keeps all the electronics in your vehicle going while you are driving while also charging the battery. If your red battery light were illuminated directly before the vehicle died, that would be another indication of a faulty alternator.

I would recommend having an inspection of your battery light issue performed by a certified mechanic as this relates to the electrical system and personal injury may result if this is not addressed in a timely manner.