diff --git a/runbot/models/build_config.py b/runbot/models/build_config.py
index 418bfa8f..dbbabdaa 100644
--- a/runbot/models/build_config.py
+++ b/runbot/models/build_config.py
@@ -334,10 +334,11 @@ class ConfigStep(models.Model):
             else:
                 build._log('test_all', 'Test tags given but not supported')
         elif self.enable_auto_tags and self.test_enable:
-            auto_tags = self.env['runbot.build.error'].disabling_tags()
-            if auto_tags:
-                test_tags = ','.join(auto_tags)
-                cmd.extend(['--test-tags', test_tags])
+            if grep(config_path, "test-tags"):
+                auto_tags = self.env['runbot.build.error'].disabling_tags()
+                if auto_tags:
+                    test_tags = ','.join(auto_tags)
+                    cmd.extend(['--test-tags', test_tags])
 
         if grep(config_path, "--screenshots"):
             cmd += ['--screenshots', '/data/build/tests']