Why doesn't it load level 4 after waiting 2 seconds, its in the build settings?

Questions & Answers
1

using UnityEngine;
using System.Collections;
public class splash: MonoBehaviour {
void Start ()
{
StartCoroutine(TestCoroutine());
}
IEnumerator TestCoroutine()
{
yield return new WaitForSeconds(2);
Application.LoadLevel(4);
}
}

2

This may help you.

// Fade out time variable.
	public float delayTime = 5;
	public bool GameMode = false;

	IEnumerator Start()
	{
		// If application is playing.
		if(GameMode || Application.isPlaying)
		{
			// Starts the time to fade.
			yield return new WaitForSeconds (delayTime);
			// Goto the function.
			Main_Menu ();
		}
	}

	public void Main_Menu()
	{
		Application.LoadLevel (4);
	}

If you satisfied give +1 for me.

3

What does the Log say?

You should try these:

Try adding the 2f to the WaitForSeconds as it takes float

yield return new WaitForSeconds(2f);

Double check the index, as it starts from 0, not 1.

So the scene 4 is actually the 5th scene in your build settings