Animator canceling a script (sway)

Hello, I create a sway script for my flashlight and attached it to the gameobject(flashlight).

Now the problem is that when I enable the animator in the gameobject(flashlight) the sway doesnt work,but when I disable it,it does work. This is the script :

 #pragma strict
 
 var flashLight : Transform;
 var xSwayAmount : float = 0.1;
 var ySwayAmount : float = 0.05;
 var maxXAmount : float = 0.35;
 var maxYAmount : float = 0.2;
 private var vector3 : Vector3;
 var smooth : float = 3.0;
 
 function Start () {
     vector3 = flashLight.localPosition;
 }
 
 function Update () {
     var fx : float = -Input.GetAxis("Mouse X") * xSwayAmount;
     var fy : float = -Input.GetAxis("Mouse Y") * ySwayAmount;
     
     if(fx > maxXAmount)
     fx = maxXAmount;
     
     if(fx< -maxXAmount)
     fx = maxXAmount;
     
     if(fy > maxYAmount)
     fy = maxYAmount;
     
     if(fy < -maxYAmount)
     fy = -maxYAmount;
     
     var detection : Vector3 = new Vector3(vector3.x + fx, vector3.y + fy, vector3.z);
     flashLight.localPosition = Vector3.Lerp(flashLight.localPosition, detection, Time.deltaTime * smooth);
 }

Has anyone got any idea why is this happening ? I need the animator to play my animations so I can't just disable it.Thank you.