Decreasing Light in Coroutine after Pickup

Hello, I'm new to Unity and programming. I'm trying to do the following: The player picks up a torch. Then the torches light-intensity slowly decreases until the torch is out. I figured this could be done with coroutines. This was my attempt:

public class PlayerTorchScript : MonoBehaviour {

 Transform Torch;
 Transform Player;
 Transform PlayerTorch;
 bool HasTorch;
 float TorchIntensity;
 Light LightComponent;

 void Start ()
 {
     Player = GameObject.FindGameObjectWithTag ("Player").GetComponent<Transform>();
     PlayerTorch = Player.GetChild (1);
     HasTorch = false;
 }

//Here the player picks up the torch

 public void OnMouseDown()
 {
     if ((transform.position - Player.position).magnitude < 3) {
         Destroy (transform.gameObject);
         PlayerTorch.gameObject.SetActive (true);
         HasTorch = true;
         LightComponent = PlayerTorch.GetComponentInChildren<Light> ();
         StartCoroutine (HasPlayerTorch ()); //Coroutine starts here
         }
 }

 IEnumerator HasPlayerTorch ()
 {
         while (LightComponent.intensity > 0f) {
             LightComponent.intensity = LightComponent.intensity - 0.25f;
             yield return new WaitForSeconds (1f);
         }
 }

}

When this script runs it decreases the light-intensity once by 0.25 units and then stops working, even though there's a while-loop. Can someone tell me what I'm doing wrong? I've tried starting the coroutine from the start and update funtion with the same problems.

Thanks in advance!