diff --git a/libraries/AP_InertialSensor/AP_InertialSensor_PX4.cpp b/libraries/AP_InertialSensor/AP_InertialSensor_PX4.cpp
index e31b4c128f..5c326cf501 100644
--- a/libraries/AP_InertialSensor/AP_InertialSensor_PX4.cpp
+++ b/libraries/AP_InertialSensor/AP_InertialSensor_PX4.cpp
@@ -163,6 +163,8 @@ bool AP_InertialSensor_PX4::_init_sensor(void)
 #else
 #if defined(CONFIG_ARCH_BOARD_PX4FMU_V2)
     _product_id = AP_PRODUCT_ID_PX4_V2;
+#elif defined(CONFIG_ARCH_BOARD_PX4FMU_V4)
+    _product_id = AP_PRODUCT_ID_PX4_V4;
 #else
     _product_id = AP_PRODUCT_ID_PX4;
 #endif