My parking sensors have been out of commission for about 6 months. I don't know why, they just stopped functioning. All they do is sound a single tone. I have them turned off right now. What could be the problem? Is it a computer issue where I can just take it to the dealer and have them reprogram it? Or is it the sensor itself that needs replacing? Wire come loose? I have no clue where to start but I do know that I'm a poor high school senior who doesn't want to pay the dealer an arm and a leg. Any help is appreciated! Thanks!