What Is The Wire Diagram For The Stereo Of A 2000 Hyundai Elantra?

Go to best buy and get a wiring harness for that car ($20). It'll plug into the factory harness of the car and each wire is listed for what it goes to. Your new radio will have a diagram in the booklet or on the radio itself. Match the wires to the new harness. Piece of cake. Don't forget! If when taking off the panels to access the radio, if if doesn't come off easy, don't force it. These  Koreans put screws in places they shouldn't be......
You weren't an eager young person who cut all the wires to the factory harness were you? Someone who took bad advice from a friend who thinks he know everything about stereos? If you did, you must trace each wire back to the speakers and label them and hardwire the new stereo that way. That's how you learn i guess. You should see how fast a wire in the wrong spot can heat up like an element and burn your car to the ground. Like a blink of an eye. Hopefully you haven't done anything yet. Good luck.