diff --git a/addons/mrp/models/mrp_workorder.py b/addons/mrp/models/mrp_workorder.py
index 11bc9879e32..3d5db258769 100644
--- a/addons/mrp/models/mrp_workorder.py
+++ b/addons/mrp/models/mrp_workorder.py
@@ -240,7 +240,7 @@ class MrpWorkorder(models.Model):
 
     @api.multi
     def write(self, values):
-        if ('date_planned_start' in values or 'date_planned_finished' in values) and any(workorder.state == 'done' for workorder in self):
+        if list(values.keys()) != ['time_ids'] and any(workorder.state == 'done' for workorder in self):
             raise UserError(_('You can not change the finished work order.'))
         return super(MrpWorkorder, self).write(values)