Collision not working in APK , but works in Unity Remote?

Hey guys , I have a script attached to a car game object that allows the player to tap the screen and then accelerate , it works fine in Unity Remote , but when I download the APK , as soon as I tap the screen , collisions go completely bezerk and the car just starts ignoring collisions , what's going on? The code I think is causing the error starts at line 48 (From main forums , I didn't get any responses)

 using UnityEngine;
 using System.Collections;
  
 public class carController : MonoBehaviour {
  
     public float carSpeed;
     public float maxPos = 2.2f;
  
     Vector3 position;
     public UIManager ui;
     public AudioManager am;
     public float MaxPosY = 3.69f;
     public GameObject anim;
     bool currntPlatformAndroid = false;
     bool heldDown = true;
     Rigidbody2D rb;
  
     void Awake(){
  
         rb = GetComponent<Rigidbody2D> ();
  
         #if UNITY_ANDROID
                 currntPlatformAndroid = true;
         #else
                 currentPlatformAndroid = false;
         #endif
  
  
         am.carSound.Play ();
  
     }
  
     void Start () {
  
         position = transform.position;
  
         if (currntPlatformAndroid == true) {
             Debug.Log ("Android");
         }
         else {
             Debug.Log ("Windows");
         }
  
  
  
     }
  
     void FixedUpdate() {
         if (Input.touchCount > 0)
         {
             transform.Translate(new Vector3(0, 1, 0) * carSpeed * Time.deltaTime);
  
         }
  
         else {
             transform.Translate(new Vector3(0, -1, 0) * carSpeed * Time.deltaTime);
  
         }
     }
     void Update()
     {
  
  
         if (currntPlatformAndroid == true)
         {
             //android specific code
             //TouchMove ();
             AccelerometerMove();
         }
  
         else {
  
             position.x += Input.GetAxis("Horizontal") * carSpeed * Time.deltaTime;
             position.y = Mathf.Clamp(position.y, -4.25f, 4.25f);
             position.x = Mathf.Clamp(position.x, -2.5f, 2.5f);
  
             transform.position = position;
         }
      
         position = transform.position;
         position.y = Mathf.Clamp(position.y, -4.25f, 4.25f);
         position.x = Mathf.Clamp(position.x, -2.5f, 2.5f);
         transform.position = position;
      
  
     }
  
      
  
  
     void OnCollisionEnter2D(Collision2D col){
  
         if (col.gameObject.tag == "EnemyCar") {
             //Destroy (gameObject);
  
  
             Instantiate(anim, transform.position, transform.rotation);
             am.explosionSound.Play();
             Destroy(anim);
             Destroy(this.gameObject);
             am.carSound.Stop();
             ui.gameOverorNot();
  
  
  
  
  
         }
     }
  
     void AccelerometerMove(){
  
         float x = Input.acceleration.x;
         Debug.Log ("X = " + x);
  
  
         if (x < -0.1f) {
             MoveLeft ();
         } else if (x > 0.1f) {
             MoveRight ();  
         }
         else {
             SetVelocityZero();
         }
  
     }
  
  
     void TouchMove(){
  
         if (Input.touchCount > 0) {
  
             Touch touch = Input.GetTouch (0);
  
             float middle = Screen.width / 2;
  
             if (touch.position.x < middle && touch.phase == TouchPhase.Began) {
                 MoveLeft ();
             }
             else if (touch.position.x > middle && touch.phase == TouchPhase.Began) {
                 MoveRight ();
             }
      
         }
  
         else {
             SetVelocityZero();
         }
  
     }
  
  
     public void MoveLeft(){
         rb.velocity = new Vector2 (-carSpeed, 0);
     }
  
     public void MoveRight(){
      
         rb.velocity = new Vector2 (carSpeed, 0);
     }
  
     public void SetVelocityZero(){
         rb.velocity = Vector2.zero;
     }
  
     /*void AccelerometerMove(){
         float x = Input.acceleration.x;
      
         Debug.Log (" X: " + x);
      
         if (x < -0.1f) {
             MoveLeft ();
         } else if (x > 0.1f) {
             MoveRight ();
         }
         else {
             SetVelocityZero();
         }
      
     }*/
  
  
  
  
  
  
  
 }
  
 

The object that script is attached to has a rigidbody and a box collider , the objects it's colliding with have box colliders.

EDIT: Just tested again and even if I just use the accelerometer and not touch the screen , the gameobject still goes bezerk and starts ignoring collisions.
My game is 2D