2000 Toyota Corolla Repair Question
Toyota Corolla Fuse Problem
You didn't hurt any relays. There are a lot of computers on your car and they all have diodes to protect them from reverse polarity. A diode is a one-way valve for electricity. They are installed backward and don't normally do anything. When you connect the battery backward, those diodes become a dead short which forces the fuse to blow to protect the rest of the circuit. You can't expect things to work until all the blown fuses are replaced. Chances are everything will work then.
For future reference, the positive battery post is larger in diameter than the negative one. The cable clamps are also different sizes.
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