What could the problem be?

I was sitting at a drive-thru window and suddenly the radio stopped playing (but did not turn off), then moments later my airbag light came on, then the light that said my VeriTrac stystem is tuned off, then the check gas cap light came on, and then my headlights began to dim and the car shut off. It would not start back up immediately. After pushing the car aside, It started back up after a few minutes of sitting turned off. I began to drive the few blocks back home. My turn signals did not work properly and after driving about two or three blocks, the whole process with the warning lights and eventual shutoff of the car happened again. Again, I had to leave it off for a few minutes and then rinse and repeat until I got home. Now, the car’s electronic locks don’t work, but the clock did for a while (is dead now), same for the car chrger for the cell phone. The car will not start. Nothing at all happens when I put in the key and turn it. The battery is about 6 months old, but in any case, this didn’t seem like a battery issue.

If nothing at all happens then I would start looking to see if the battery is charged. If is not, suspect an alternator has failed without the “idiot light” coming on. This is common with GM products that I have seen and experienced personally.

What is the make, year and model along with milage?

I don’t understand why you would come here with a puzzle, such as this, and you haven’t done, or had someone do, something as simple as opening the hood and looking the engine compartment over for something amiss. What if you were to open the hood, look, and see a drive belt broke/missing, or wires obviously damaged?
You can look, or have someone to look, and tell us, can’t you? Does this sound like an outlandish request?

Actually, this DOES seem like a battery issue. The battery may be only six months old, but how old is the alternator? If the alternator was not charging the battery sufficiently, the battery can die just as you described.

I suggest you have someone test both the battery and the charging system.

May we please have the year, make, model, and odometer reading of the vehicle in question?

When you refer to the “check gas cap” light, do you mean the “check engine” light or is there a special light just for the gas cap?

You Have Not Given Enough Information. What Kind Of Drive-Thru Window … Bank, Restaurant, What?

Also, while you’re at it, why don’t you give the make, model, year, and miles of this car(?). Also tell which engine you have, if you know, and manual or automatic transmission. Sometimes people with similar vehicles and similar experiences can help you. Sometimes problems are vehicle specific.

Yeah, that would be useful information. It’s a 2002 Ford Focus ZX5 with 89K miles

oddly enough, there is a light specifically for the gas cap, which I didn’t know until it turned on. The check engine light never did actually turn on.

This is a charging system problem, the battery is not being charged and the electrical sysetm is running off the battery until it’s dead.

The alternator is supposed to power all of these systems when the engine is running but since the alternator is not charging, everything draws off the battery until it’s dead.

I agree it is related to the battery or the charging system. If the battery and alternator test fine, examine the wires and cables in between. If one of them is getting too hot to touch, consider replacing it.

Many auto parts stores will test your battery and alternator for free. Give that a try.

The battery is fine, but now totally discharged. The miraculous coming back to life is what a good battery can do when it gets a break from the discharge. The battery is warm and will recover enough voltage and amps to run the car for a bit then it will discharge again.

The charging system has failed and the battery is not getting a charge. Perhaps the belt broke, but that should impact power steering if the car has a serpentine belt. If the belt is intact and the alternator is turning then there is a short or fault somewhere, perhaps the entire alternator is shot; not farfetched after 90K miles. You can charge the battery if you have access to a charger and AC power and then drive the car to a shop for an evaluation.

Don’t buy another battery, it won’t get you any further than recharging the battery you have now.

Automotive batteries are not made to be completely discharged. If this battery has been completely discharged I would not trust it.