diff --git a/factory_common.mk b/factory_common.mk
index ecd1232..391fa54 100644
--- a/factory_common.mk
+++ b/factory_common.mk
@@ -73,4 +73,7 @@
 
 # PixelLogger for RF testing
 PRODUCT_PACKAGES_DEBUG += \
-    PixelLogger \
+    PixelLogger
+
+# Modem userdebug
+include device/google/gs101/modem/userdebug.mk