diff --git a/scripts/build-aml-prebuilts.sh b/scripts/build-aml-prebuilts.sh
index de22c45..e6e541e 100755
--- a/scripts/build-aml-prebuilts.sh
+++ b/scripts/build-aml-prebuilts.sh
@@ -77,6 +77,9 @@
 # CrossHost: linux_bionic
 # CrossHostArch: x86_64
 #   -  Enable Bionic on host as ART needs prebuilts for it.
+# VendorVars.art_mdoule.source_build
+#   -  TODO(b/172480615): Change default to false when platform uses ART Module
+#      prebuilts by default.
 cat > ${SOONG_VARS}.new << EOF
 {
     "BuildNumberFile": "build_number.txt",
@@ -98,7 +101,7 @@
 
     "VendorVars": {
         "art_module": {
-            "source_build": "${ENABLE_ART_SOURCE_BUILD:-false}"
+            "source_build": "${ENABLE_ART_SOURCE_BUILD:-true}"
         }
     }
 }