diff --git a/update_manager/boxed_value_unittest.cc b/update_manager/boxed_value_unittest.cc
index 99d578c..212db36 100644
--- a/update_manager/boxed_value_unittest.cc
+++ b/update_manager/boxed_value_unittest.cc
@@ -161,6 +161,9 @@
 }
 
 TEST(UmBoxedValueTest, ConnectionTypeToString) {
+  EXPECT_EQ(
+      "Disconnected",
+      BoxedValue(new ConnectionType(ConnectionType::kDisconnected)).ToString());
   EXPECT_EQ("ethernet",
             BoxedValue(new ConnectionType(ConnectionType::kEthernet))
             .ToString());