i put a new battery in my girl friends moms car. 96 legacy. after i did there was a clicking noise under the dash almost sounded like a turn signal. it did it with the car off or on. i found this black box to the left of the brake pedal. on one of the wires going to it was a little button. after pressing it the noise stopped.

what is this box.

It sounds like it may be a security system. The switch you found may be the reset switch. That is my guess.

 

Matt D

Yup, it's the factory door lock system

Put the key in the ignition, turn to to the ON position and press the button under the dash. If you got an aftermarket security system, u can unplug the factory system. it's a 5x5 box in the foot well, near the foot rest.