Problem loading Composer class to web server

Question

I’m having trouble correctly running a site developed with the MVC architecture on web server. Locally, everything is going well. The folder structure is as follows:

• public_html(public directory of the server):
  • index php.
  • css
  • js
• App:
  • App
  • Vendor
  • Composer.json
  • Composer.lock
  • Composer.phar

The index is as follows:

<?php

     //ini_set('error_reporting', 'E_STRICT');

     require_once "../App/vendor/autoload.php";

     $route = new \App\Route;
    


?>

Remembering that, unfortunately, I have no control over enabling php errors in this hosting. Always falls on blank screen or Internal Server Error.