Why lighting isn't working in Three.js?

I don't understand why the lighting does not work in my code. I downloaded a simple OBJ. file to test the OBJLoader but the model isn't affected. Before I edited the lighting more, at least the Ambient Lighting would work. Maybe the OBJ. model needs a texture?

            var container, stats;

        var camera, scene, renderer, controls;


        init();
        animate();


        function init() {

            container = document.createElement( 'div' );
            document.body.appendChild( container );

            scene = new THREE.Scene();

            camera = new THREE.PerspectiveCamera( 45, window.innerWidth / window.innerHeight, 1, 2000 );
            camera.position.z = 2.5;
            scene.add( camera );

            controls = new THREE.TrackballControls( camera );

            controls.rotateSpeed = 2.0;
            controls.zoomSpeed = 1.2;
            controls.panSpeed = 0.0;

            controls.noZoom = false;
            controls.noPan = true;

            controls.staticMoving = true;
            controls.dynamicDampingFactor = 0.3;

            controls.keys = [ 65, 83, 68 ];

            controls.addEventListener( 'change', render );

            var ambient = new THREE.AmbientLight( 0x020202 );
            scene.add( ambient );

            directionalLight = new THREE.DirectionalLight( 0xffffff );
            directionalLight.position.set( 1, 1, 0.5 ).normalize();
            scene.add( directionalLight );

            pointLight = new THREE.PointLight( 0xffaa00 );
            pointLight.position.set( 0, 0, 0 );
            scene.add( pointLight );

            sphere = new THREE.SphereGeometry( 100, 16, 8 );
            lightMesh = new THREE.Mesh( sphere, new THREE.MeshBasicMaterial( { color: 0xffaa00 } ) );
            lightMesh.scale.set( 0.05, 0.05, 0.05 );
            lightMesh.position = pointLight.position;
            scene.add( lightMesh );


            var loader = new THREE.OBJLoader();
            load