Link Health Bar and TNT Damage scripts together

[namekaw]

I have a script that is attached to a car which gives is health and has a bar associated with it. I also have TNT which causes damage. I am not sure how to make the TNT subtract damage from the car health. Here is my explosion script which I found in a tutorial and changed to the way I thought would work. It has a bit to connect scripts but I am not sure the correct syntax to make it work-

enum ExplosionTypes {TNT, Nitro, Other}
var explosionType : ExplosionTypes;
var explosion : Transform;
var damage : float;
var hitPoints : float = 0;
var deadReplacement : Rigidbody;
var explosionFX : AudioClip;
private var explodeSecs : float = 1;
private var duration : float = 1;
private var isTNT = false;

Function OnCollisionEnter (col : Collision){

var contact : ContactPoint = col.contacts[0];
var rot : Quaternion = Quaternion.FromToRotation(Vector3.up,contact.normal);
var pos : Vector3 = contact.point;

if(col.collider.gameObject.tag == "Stockcar" || col.collider.gameObject.tag == "TNT"){
   if(explosionType == ExplosionTypes.Nitro){
     Instantiate(explosion,pos,rot);
     Explode();
     audio.PlayOneShot(explosionFX);
     Destroy(gameObject);
     col.collider.SendMessage("ApplyDamage",damage,SendMessageOptions.DontRequireReceiver);
     }
   if(explosionType == ExplosionTypes.TNT){
     isTNT = true;
   }
   if(explosionType == ExplosionTypes.Other){
     Instantiate(explosion,pos,rot);
     Explode();
     audio.PlayOneShot(explosionFX);
     Destroy(gameObject);
     col.collider.SendMessage("ApplyDamage",damage,SendMessageOptions.DontRequireReceiver);
   }
   }

}

function Update () {
var t : float = Mathf.PingPong (Time.time, duration) / duration;
if(isTNT){
renderer.material.color = Color.Lerp(Color.red,Color.gray,t);
}
}

function Explode(){
var expl : Transform;
expl = Instantiate(explosion,transform.position, transform.rotation);
Destroy(gameObject);
if(isTNT) isTNT = false;
}

@script RequireComponent(AudioSource);

Thanks

[Hrethric]

You have to give at least one of the objects a RigidBody, and then do this:

Unity - Scripting API: MonoBehaviour.OnCollisionEnter(Collision)

Depending on how you set up the logic, you will either need figure out what the car collided with, and decrease its health based on the result, or you will want to find what the TNT exploded, and do damage based on that.