Why isn`t my 2D AddTorque working?

Hello I have this C# script attached to player in Fixed Update:

rigidbody2D.AddTorque(Input.GetAxis ("Horizontal") * 5f);

It just won`t work. AddForce works and everything else in that script just not this.

What I have tried so far:

if(Input.GetButton("Horizontal"))
     rigidbody2D.AddTorque(5f);

Even this won`t work in Update without any key check:

rigidbody2D.AddTorque(5f);

Yes script is attached, Yes object has Rigidbody2D. As I said, AddForce works, just torque not.
Is Kinematic and Fixed angle are Checked OFF.

Please help I am getting hopeless.

THE SOLUTION:

2D addTorque is bugged.

When you do this:

public float rotationSpeed; //And now you assaign it in inspector
void FixedUpdate()
{
     rigidbody2D.AddTorque(Input.GetAxis ("Horizontal") * rotationSpeed);
}

It wont work. Because its bugged. But when you don`t assaign it in the inspector, it works fine.

void FixedUpdate()
{
     float rotationSpeed = 5.0f; 
     rigidbody2D.AddTorque(Input.GetAxis ("Horizontal") * rotationSpeed);
}

This works. At least for me.

Maybe the value calculated with " Input.GetAxis (“Horizontal”) * 5f " is too small for the mass of the object, try a very large one.

Also call WakeUp after adding the torque: