diff --git a/core/modules/update/tests/modules/update_test/lib/Drupal/update_test/Controller/UpdateTestController.php b/core/modules/update/tests/modules/update_test/lib/Drupal/update_test/Controller/UpdateTestController.php
new file mode 100644
index 0000000..613cfd2
--- /dev/null
+++ b/core/modules/update/tests/modules/update_test/lib/Drupal/update_test/Controller/UpdateTestController.php
@@ -0,0 +1,31 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\update_test\Controller\UpdateTestController.
+ */
+
+namespace Drupal\update_test\Controller;
+use Symfony\Component\HttpFoundation\Response;
+
+/**
+ * Provides different routes of the update_test module.
+ */
+class UpdateTestController {
+
+
+  /**
+   * Displays an Error 503 (Service unavailable) page.
+   *
+   * @return \Symfony\Component\HttpFoundation\Response
+   *   Returns the response with a special header.
+   */
+  public function updateError() {
+    $response = new Response();
+    $response->setStatusCode(503);
+    $response->headers->set('Status', '503 Service unavailable');
+
+    return $response;
+  }
+
+}
diff --git a/core/modules/update/tests/modules/update_test/update_test.module b/core/modules/update/tests/modules/update_test/update_test.module
index 31ee72d..b87b02c 100644
--- a/core/modules/update/tests/modules/update_test/update_test.module
+++ b/core/modules/update/tests/modules/update_test/update_test.module
@@ -29,12 +29,6 @@ function update_test_menu() {
     'access callback' => TRUE,
     'type' => MENU_CALLBACK,
   );
-  $items['503-error'] = array(
-    'title' => t('503 Service unavailable'),
-    'page callback' => 'update_callback_service_unavailable',
-    'access callback' => TRUE,
-    'type' => MENU_CALLBACK,
-  );
 
   return $items;
 }
@@ -163,13 +157,3 @@ function update_test_filetransfer_info() {
     ),
   );
 }
-
-/**
- * Page callback: Displays an Error 503 (Service unavailable) page.
- *
- * @see update_test_menu()
- */
-function update_callback_service_unavailable() {
-  drupal_add_http_header('Status', '503 Service unavailable');
-  print "503 Service Temporarily Unavailable";
-}
diff --git a/core/modules/update/tests/modules/update_test/update_test.routing.yml b/core/modules/update/tests/modules/update_test/update_test.routing.yml
new file mode 100644
index 0000000..b60d143
--- /dev/null
+++ b/core/modules/update/tests/modules/update_test/update_test.routing.yml
@@ -0,0 +1,6 @@
+update_test_503:
+  pattern: '/503-error'
+  defaults:
+    _controller: 'Drupal\update_test\Controller\UpdateTestController::updateError'
+  requirements:
+    _access: 'TRUE'