The sensitivity is probably set to the lowest setting. You have to figure out where the "brain" of the alarm is installed and follow all of the wires grouped in 3 until you find the small,clear box. Usually it has a light on it that blinks when it is tripped. It is usually zip tied to the existing wires from your car so it can absorb the vibration. After you find it, turn the dial to the "+" side as desired.