diff --git a/automotive/vehicle/aidl/Android.bp b/automotive/vehicle/aidl/Android.bp
index 4b2d2b8..dfc8125 100644
--- a/automotive/vehicle/aidl/Android.bp
+++ b/automotive/vehicle/aidl/Android.bp
@@ -27,7 +27,7 @@
     srcs: [
         "android/hardware/automotive/vehicle/*.aidl",
     ],
-    frozen: false,
+    frozen: true,
     stability: "vintf",
     backend: {
         cpp: {
@@ -58,6 +58,10 @@
             version: "3",
             imports: [],
         },
+        {
+            version: "4",
+            imports: [],
+        },
 
     ],
     host_supported: true,