Disabling/Enabling constant force via script??

I need to be able to disable/enable constant force with a script. Any ideas on why it won’t work? Thanks in advance! Btw, I will be adding whomever fixes this’ name to the credits of our game :smiley: Brady

   Code:
    
    #pragma strict
    function Start () {
    
    }
    
    function FixedUpdate () { if (Input.GetKeyDown(KeyCode.W)); constantForce.enabled = true; else if (Input.GetKeyDown(KeyCode.S)); constantForce.enabled = false; }

if (Input.GetKeyDown(KeyCode.W)); constantForce.enabled = true;
This is wrong. If statement is doing nothing because of the semi-colon. It should be

if (Input.GetKeyDown(KeyCode.W)) constantForce.enabled = true;

Same for else statement.