diff --git a/modules/system/system.js b/modules/system/system.js
new file mode 100644
index 00000000000..a44d3ef2a44
--- /dev/null
+++ b/modules/system/system.js
@@ -0,0 +1,24 @@
+/**
+ * Internal function to check using Ajax if clean URLs can be enabled on the
+ * settings page.
+ *
+ * This function is not used to verify whether or not clean URLs
+ * are currently enabled.
+ */
+Drupal.cleanURLsSettingsCheck = function() {
+  var url = location.pathname +"admin/settings/clean-urls";
+  $("#clean-url .description span").html('<div id="testing">'+ Drupal.settings.cleanURL.testing +"</div>");
+  $("#clean-url p").hide();
+  $.ajax({url: location.protocol +"//"+ location.hostname + url, type: "GET", data: " ", complete: function(response) {
+    $("#testing").toggle();
+    if (response.status == 200) {
+      // Check was successful.
+      $("#clean-url input.form-radio").attr("disabled", "");
+      $("#clean-url .description span").append('<div class="ok">'+ Drupal.settings.cleanURL.success +"</div>");
+    }
+    else {
+      // Check failed.
+      $("#clean-url .description span").append('<div class="warning">'+ Drupal.settings.cleanURL.failure +"</div>");
+    }
+  }});
+}