NullReferenceException Confusion

Questions & Answers
1

Hello. I have a footsteps script I found, but I have a problem. Every time my frame updates, I have a single NullReferenceException. This eats up a HUGE amount of my game’s performance. Please help! Here the code:

#pragma strict

var inWater : boolean = false;
var waterStepSound : AudioClip;

var waterTimer : float = 0;
var waterCool : float = 0.6;

private var chMotor : CharacterMotor;
private var controller : CharacterController;

function Start()
{
	chMotor = GetComponent(CharacterMotor);
	controller = GetComponent(CharacterController);
}

function Update()
{
	if(controller.velocity.magnitude > 0 && Input.GetKey(KeyCode.LeftShift))
	{
		chMotor.movement.maxForwardSpeed = 10;
		chMotor.movement.maxSidewaysSpeed = 10;
	}
	
	else
	{	
		chMotor.movement.maxForwardSpeed = 7;
		chMotor.movement.maxSidewaysSpeed = 6;
	}
	
	if(controller.velocity.magnitude > 0 && inWater == true)
	{
		WaterSound();
	}
	
	if(controller.velocity.magnitude > 0 && Input.GetKey(KeyCode.LeftShift) && inWater == true)
	{
		waterCool = 0.4;
		WaterSound();
	}
	
	else
	{
		waterCool = 0.6;
	}
	
	if(waterTimer > 0)
	{
		waterTimer -= Time.deltaTime;
	}
	
	if(waterTimer < 0)
	{
		waterTimer = 0;
	}
}

function WaterSound()
{
	if(waterTimer == 0)
	{
		audio.PlayOneShot(waterStepSound);
		waterTimer = waterCool;
	}
}

And the other script it is working with:

#pragma strict

private var footsteps : PlayerFootsteps;

function Start()
{
	footsteps = GameObject.Find("First Person Controller").GetComponent(PlayerFootsteps);
}

function OnTriggerEnter (Col : Collider)
{
	if(Col.gameObject.tag == "Player")
	{
		footsteps.inWater = true;
	}
}

function OnTriggerExit (Col : Collider)
{
	if(Col.gameObject.tag == "Player")
	{
		footsteps.inWater = false;
	}
}
2

It looks like chMotor is null when executing that line.

This would be the case is GetComponent(CharacterMotor) returns null in Start().

Is a CharacterMotor script attached to this GameObject? Is the script disabled?