What does the little car with lines coming from the back of it mean?

If they are squiggly lines, it may be anti-lock brake system--however, I'm just guessing.

You have a brake or tail light out. Good guess anyway, tx.
Try this: Don't even start the car, just have the key on so the other dash light are on.
Now step on the brake. If the icon illuminated when doing that, it's a brake light issue.
If it didn't come on, then turn on your headlights to see if it lights up then.

It's either "traction active" or a "Light out". Traction active only comes on "briefly" . The light one will be on all the time until fixed. The "lic plate" lamp seems to be the first to go.

Remember, if your driving in snow or rain turn traction control OFF.