diff --git a/vmware_nsx/plugins/nsx_v3/plugin.py b/vmware_nsx/plugins/nsx_v3/plugin.py
index 260ba698c7..5e6990057d 100644
--- a/vmware_nsx/plugins/nsx_v3/plugin.py
+++ b/vmware_nsx/plugins/nsx_v3/plugin.py
@@ -21,6 +21,7 @@ from neutron_lib.exceptions import port_security as psec_exc
 from neutron.api.rpc.agentnotifiers import dhcp_rpc_agent_api
 from neutron.api.rpc.handlers import dhcp_rpc
 from neutron.api.rpc.handlers import metadata_rpc
+from neutron.api.v2 import base
 from neutron.common import rpc as n_rpc
 from neutron.common import topics
 from neutron.db import _resource_extend as resource_extend
@@ -71,6 +72,7 @@ from oslo_utils import excutils
 from oslo_utils import importutils
 from oslo_utils import uuidutils
 from sqlalchemy import exc as sql_exc
+import webob.exc
 
 from vmware_nsx._i18n import _
 from vmware_nsx.api_replay import utils as api_replay_utils
@@ -174,6 +176,7 @@ class NsxV3Plugin(agentschedulers_db.AZDhcpAgentSchedulerDbMixin,
         router=l3_db_models.Router,
         floatingip=l3_db_models.FloatingIP)
     def __init__(self):
+        self._extend_fault_map()
         self._extension_manager = managers.ExtensionManager()
         super(NsxV3Plugin, self).__init__()
         # Bind the dummy L3 notifications
@@ -246,6 +249,22 @@ class NsxV3Plugin(agentschedulers_db.AZDhcpAgentSchedulerDbMixin,
         # Register NSXv3 trunk driver to support trunk extensions
         self.trunk_driver = trunk_driver.NsxV3TrunkDriver.create(self)
 
+    def _extend_fault_map(self):
+        """Extends the Neutron Fault Map.
+
+        Exceptions specific to the NSX Plugin are mapped to standard
+        HTTP Exceptions.
+        """
+        base.FAULT_MAP.update({nsx_lib_exc.ManagerError:
+                               webob.exc.HTTPBadRequest,
+                               nsx_lib_exc.ServiceClusterUnavailable:
+                               webob.exc.HTTPServiceUnavailable,
+                               nsx_lib_exc.ClientCertificateNotTrusted:
+                               webob.exc.HTTPBadRequest,
+                               nsx_exc.SecurityGroupMaximumCapacityReached:
+                               webob.exc.HTTPBadRequest,
+                               })
+
     def _init_fwaas(self):
         # Bind FWaaS callbacks to the driver
         self.fwaas_callbacks = fwaas_callbacks.Nsxv3FwaasCallbacks(self.nsxlib)
diff --git a/vmware_nsx/tests/unit/extensions/test_securitygroup.py b/vmware_nsx/tests/unit/extensions/test_securitygroup.py
index a95bc1a530..ec74675d24 100644
--- a/vmware_nsx/tests/unit/extensions/test_securitygroup.py
+++ b/vmware_nsx/tests/unit/extensions/test_securitygroup.py
@@ -135,7 +135,7 @@ class TestSecurityGroupsNoDynamicCriteria(test_nsxv3.NsxV3PluginTestCaseMixin,
                 res = self._create_port(self.fmt, net['network']['id'])
                 res_body = self.deserialize(self.fmt, res)
 
-        self.assertEqual(500, res.status_int)
+        self.assertEqual(400, res.status_int)
         self.assertEqual('SecurityGroupMaximumCapacityReached',
                          res_body['NeutronError']['type'])
 
@@ -161,7 +161,7 @@ class TestSecurityGroupsNoDynamicCriteria(test_nsxv3.NsxV3PluginTestCaseMixin,
                     res = req.get_response(self.api)
                     res_body = self.deserialize(self.fmt, res)
 
-        self.assertEqual(500, res.status_int)
+        self.assertEqual(400, res.status_int)
         self.assertEqual('SecurityGroupMaximumCapacityReached',
                          res_body['NeutronError']['type'])