diff --git a/boards/px4/fmu-v4/init/rc.board_sensors b/boards/px4/fmu-v4/init/rc.board_sensors
index d44dba215e..c30a94aaf9 100644
--- a/boards/px4/fmu-v4/init/rc.board_sensors
+++ b/boards/px4/fmu-v4/init/rc.board_sensors
@@ -68,3 +68,6 @@ then
 	# BMI160 internal SPI bus
 	bmi160 start
 fi
+
+# External RM3100 (I2C or SPI)
+rm3100 start