diff --git a/src/drivers/ll40ls/ll40ls.cpp b/src/drivers/ll40ls/ll40ls.cpp
index 8591c4dee3..51e230f189 100644
--- a/src/drivers/ll40ls/ll40ls.cpp
+++ b/src/drivers/ll40ls/ll40ls.cpp
@@ -97,7 +97,7 @@ LidarLite *get_dev(const bool use_i2c, const int bus)
 	LidarLite *g_dev = nullptr;
 
 	if (use_i2c) {
-		g_dev = static_cast<LidarLite *>(bus == PX4_I2C_BUS_ONBOARD ? g_dev_int : g_dev_ext);
+		g_dev = static_cast<LidarLite *>(bus == PX4_I2C_BUS_EXPANSION ? g_dev_ext : g_dev_int);
 
 		if (g_dev == nullptr) {
 			errx(1, "i2c driver not running");
@@ -231,11 +231,12 @@ void start(const bool use_i2c, const int bus)
 
 fail:
 
+#ifdef PX4_I2C_BUS_ONBOARD
 	if (g_dev_int != nullptr && (bus == -1 || bus == PX4_I2C_BUS_ONBOARD)) {
 		delete g_dev_int;
 		g_dev_int = nullptr;
 	}
-
+#endif
 	if (g_dev_ext != nullptr && (bus == -1 || bus == PX4_I2C_BUS_EXPANSION)) {
 		delete g_dev_ext;
 		g_dev_ext = nullptr;
@@ -255,17 +256,16 @@ fail:
 void stop(const bool use_i2c, const int bus)
 {
 	if (use_i2c) {
-		if (bus == PX4_I2C_BUS_ONBOARD) {
-			if (g_dev_int != nullptr) {
-				delete g_dev_int;
-				g_dev_int = nullptr;
-			}
-
-		} else {
+		if (bus == PX4_I2C_BUS_EXPANSION) {
 			if (g_dev_ext != nullptr) {
 				delete g_dev_ext;
 				g_dev_ext = nullptr;
 			}
+		} else {
+			if (g_dev_int != nullptr) {
+				delete g_dev_int;
+				g_dev_int = nullptr;
+			}
 		}
 
 	} else {
@@ -293,7 +293,7 @@ test(const bool use_i2c, const int bus)
 	const char *path;
 
 	if (use_i2c) {
-		path = ((bus == PX4_I2C_BUS_ONBOARD) ? LL40LS_DEVICE_PATH_INT : LL40LS_DEVICE_PATH_EXT);
+		path = ((bus == PX4_I2C_BUS_EXPANSION) ? LL40LS_DEVICE_PATH_EXT : LL40LS_DEVICE_PATH_INT);
 
 	} else {
 		path = LL40LS_DEVICE_PATH_PWM;
@@ -366,7 +366,7 @@ reset(const bool use_i2c, const int bus)
 	const char *path;
 
 	if (use_i2c) {
-		path = ((bus == PX4_I2C_BUS_ONBOARD) ? LL40LS_DEVICE_PATH_INT : LL40LS_DEVICE_PATH_EXT);
+		path = ((bus == PX4_I2C_BUS_EXPANSION) ? LL40LS_DEVICE_PATH_EXT : LL40LS_DEVICE_PATH_INT);
 
 	} else {
 		path = LL40LS_DEVICE_PATH_PWM;
diff --git a/src/drivers/px4flow/px4flow.cpp b/src/drivers/px4flow/px4flow.cpp
index 18acccc00c..5b7f1e5557 100644
--- a/src/drivers/px4flow/px4flow.cpp
+++ b/src/drivers/px4flow/px4flow.cpp
@@ -694,7 +694,9 @@ start()
 #ifdef PX4_I2C_BUS_ESC
 			PX4_I2C_BUS_ESC,
 #endif
+#ifdef PX4_I2C_BUS_ONBOARD
 			PX4_I2C_BUS_ONBOARD,
+#endif
 			-1
 		};