When I press the fog light button there is this weird sound coming from the back of the truck. When the fog light button is pressed, it activates something in the cargo door or the back passenger side of the car. Other observances: - It doesn't sound like the rear wiper, that works great. - It no more noise after fog light is turned on for the first time starting car. - Fog lights work great. - Don't see a problem like this when searching forums or Google.