diff --git a/ROMFS/px4fmu_common/init.d/rc.interface b/ROMFS/px4fmu_common/init.d/rc.interface
index e305713377..b19ec75ff8 100644
--- a/ROMFS/px4fmu_common/init.d/rc.interface
+++ b/ROMFS/px4fmu_common/init.d/rc.interface
@@ -123,9 +123,9 @@ then
 		fi
 	fi
 
-	if [ $MIXER_AUX_FILE != none -a $FMU_MODE == pwm ]
+	if [ $MIXER_AUX_FILE != none ]
 	then
-		if fmu mode_pwm
+		if fmu mode_$AUX_MODE
 		then
 			if [ -e $OUTPUT_AUX_DEV ]
 			then
diff --git a/ROMFS/px4fmu_common/init.d/rcS b/ROMFS/px4fmu_common/init.d/rcS
index 910f5f6291..dac23fe6b7 100644
--- a/ROMFS/px4fmu_common/init.d/rcS
+++ b/ROMFS/px4fmu_common/init.d/rcS
@@ -127,6 +127,7 @@ then
 	set FAILSAFE_AUX none
 	set MK_MODE none
 	set FMU_MODE pwm
+	set AUX_MODE pwm
 	set MAVLINK_F default
 	set EXIT_ON_END no
 	set MAV_TYPE none
@@ -451,17 +452,6 @@ then
 		fi
 	fi
 
-	# Start sensors depending on the interface being up
-	if param compare SENS_EN_LL40LS 1
-	then
-		if pwm_input start
-		then
-			if ll40ls start pwm
-			then
-			fi
-		fi
-	fi
-
 	if [ $MAVLINK_F == default ]
 	then
 		# Normal mode, use baudrate 57600 (default) and data rate 1000 bytes/s
@@ -517,6 +507,19 @@ then
 	#
 	sh /etc/init.d/rc.logging
 
+	# Sensors on the PWM interface bank
+	if param compare SENS_EN_LL40LS 1
+	then
+		if pwm_input start
+		then
+			if ll40ls start pwm
+			then
+				# Reserve the last two pins
+				set AUX_MODE pwm4
+			fi
+		fi
+	fi
+
 	#
 	# Start up ARDrone Motor interface
 	#