diff --git a/ROMFS/px4fmu_common/init.d/rcS b/ROMFS/px4fmu_common/init.d/rcS
index a4908a1a74..a6d2d64a3f 100644
--- a/ROMFS/px4fmu_common/init.d/rcS
+++ b/ROMFS/px4fmu_common/init.d/rcS
@@ -38,7 +38,9 @@ mount -t procfs /proc
 #
 # Start CDC/ACM serial driver
 #
-sercon
+if sercon
+then
+fi
 
 #
 # Default to auto-start mode.