Wrote a car script that wont work

Here's the script

 #pragma strict
 var wheelFL : WheelCollider;
 var wheelFR : WheelCollider;
 var wheelRL : WheelCollider;
 var wheelRR : WheelCollider;
 var maxTorque : float  = 50;
 function Start () {
 
 }
 
 function FixedUpdate () {
 wheelRR.motorTorque = maxTorque * Input.GetAxis("Vertical");
 wheelRL.motorTorque = maxTorque * Input.GetAxis("Vertical");
 wheelFL.steerAngle = 10 * Input.GetAxis("Horizontal");
 wheelFR.steerAngle = 10 * Input.GetAxis("Horizontal");
 }