diff --git a/main.py b/main.py
index 5433d7e..a61706d 100644
--- a/main.py
+++ b/main.py
@@ -81,6 +81,8 @@ class TestHTTP(TestCase):
     def _check_status(self, resp: urllib3.HTTPResponse) -> None:
         logging.debug(resp.headers.items())
         logging.debug(resp.data)
+        if resp.status == 400:
+            logging.warning(' x-full-error = %s', resp.getheader('x-full-error'))
         self.assertEqual(resp.status, 200)
 
     def tearDown(self) -> None: