diff --git a/addons/web/static/src/js/views/form_view.js b/addons/web/static/src/js/views/form_view.js
index 0330c5d95cb..640644b482a 100644
--- a/addons/web/static/src/js/views/form_view.js
+++ b/addons/web/static/src/js/views/form_view.js
@@ -55,7 +55,6 @@ var FormView = View.extend(common.FieldManagerMixin, {
         this.fields = {};
         this.fields_order = [];
         this.datarecord = {};
-        this._onchange_specs = {};
         this.onchanges_mutex = new utils.Mutex();
         this.default_focus_field = null;
         this.default_focus_button = null;
@@ -75,7 +74,6 @@ var FormView = View.extend(common.FieldManagerMixin, {
         this.rendering_engine = new FormRenderingEngine(this);
         this.set({actual_mode: this.options.initial_mode});
         this.has_been_loaded.done(function() {
-            self._build_onchange_specs();
             self.on("change:actual_mode", self, self.toggle_buttons);
             self.on("change:actual_mode", self, self.toggle_sidebar);
         });
@@ -318,8 +316,11 @@ var FormView = View.extend(common.FieldManagerMixin, {
         this.update_pager(); // the mode must be actualized before updating the pager
         return $.when.apply(null, set_values).then(function() {
             if (!record.id) {
-                // trigger onchanges
-                self.do_onchange(null);
+                // trigger onchange for new record after x2many with non-embedded views are loaded
+                var fields_loaded = _.pluck(self.fields, 'is_loaded');
+                $.when.apply(null, fields_loaded).done(function() {
+                    self.do_onchange(null);
+                });
             }
             self.on_form_changed();
             self.rendering_engine.init_fields().then(function() {
@@ -333,7 +334,7 @@ var FormView = View.extend(common.FieldManagerMixin, {
                 } else {
                     self.do_push_state({});
                 }
-                self.$el.removeClass('oe_form_dirty');                
+                self.$el.removeClass('oe_form_dirty');
             });
          });
     },
@@ -381,7 +382,24 @@ var FormView = View.extend(common.FieldManagerMixin, {
         _.each(this.fields, function(field, name) {
             self._onchange_fields.push(name);
             self._onchange_specs[name] = find(name, field.node);
-            _.each(field.field.views, function(view) {
+
+            // we get the list of first-level fields of x2many firstly by
+            // getting them from the field embedded views, then if no embedded
+            // view is present for a loaded view, we get them from the default
+            // view that has been loaded
+
+            // gather embedded view objects
+            var views = _.clone(field.field.views);
+            // also gather default view objects
+            if (field.viewmanager) {
+                _.each(field.viewmanager.views, function(view, view_type) {
+                    // add default view if it was not embedded and it is loaded
+                    if (views[view_type] === undefined && view.controller) {
+                        views[view_type] = view.controller.fields_view;
+                    }
+                });
+            }
+            _.each(views, function(view) {
                 _.each(view.fields, function(_, subname) {
                     self._onchange_specs[name + '.' + subname] = find(subname, view.arch);
                 });
@@ -410,6 +428,9 @@ var FormView = View.extend(common.FieldManagerMixin, {
 
     do_onchange: function(widget) {
         var self = this;
+        if (self._onchange_specs === undefined) {
+            self._build_onchange_specs();
+        }
         var onchange_specs = self._onchange_specs;
         try {
             var def = $.when({});
diff --git a/odoo/addons/test_new_api/tests/test_onchange.py b/odoo/addons/test_new_api/tests/test_onchange.py
index 0301ca2b3e4..a6e2bff1b35 100644
--- a/odoo/addons/test_new_api/tests/test_onchange.py
+++ b/odoo/addons/test_new_api/tests/test_onchange.py
@@ -307,12 +307,7 @@ class TestOnChange(common.TransactionCase):
 
         # When one2many domain contains non-computed field, things are ok
         self.assertEqual(result['value']['important_messages'],
-                         [(5,)] + [(1, msg.id, {
-                                    'name': msg.name,
-                                    'body': msg.body,
-                                    'author': (msg.author.id, msg.author.display_name),
-                                    'size': msg.size
-                                    }) for msg in discussion.important_messages])
+                         [(5,)] + [(4, msg.id) for msg in discussion.important_messages])
 
         # But here with commit 5676d81, we get value of: [(2, email.id)]
         self.assertEqual(
diff --git a/odoo/fields.py b/odoo/fields.py
index c004b640cd2..2f898221e99 100644
--- a/odoo/fields.py
+++ b/odoo/fields.py
@@ -2133,7 +2133,7 @@ class One2many(_RelationalMulti):
     _description_relation_field = property(attrgetter('inverse_name'))
 
     def convert_to_onchange(self, value, record, fnames=()):
-        fnames = set(fnames or value.fields_view_get()['fields'])
+        fnames = set(fnames or ())
         fnames.discard(self.inverse_name)
         return super(One2many, self).convert_to_onchange(value, record, fnames)