diff --git a/src/Symfony/Component/DependencyInjection/Loader/YamlFileLoader.php b/src/Symfony/Component/DependencyInjection/Loader/YamlFileLoader.php
index 7240fb5812985..79adcf2161b7a 100644
--- a/src/Symfony/Component/DependencyInjection/Loader/YamlFileLoader.php
+++ b/src/Symfony/Component/DependencyInjection/Loader/YamlFileLoader.php
@@ -476,6 +476,9 @@ private function parseDefinition($id, $service, $file, array $defaults)
                     $args = isset($call[1]) ? $this->resolveServices($call[1], $file) : array();
                 }
 
+                if (!is_array($args)) {
+                    throw new InvalidArgumentException(sprintf('The second parameter for function call "%s" must be an array of its arguments for service "%s" in %s. Check your YAML syntax.', $method, $id, $file));
+                }
                 $definition->addMethodCall($method, $args);
             }
         }