diff --git a/libraries/AP_AHRS/AP_AHRS_config.h b/libraries/AP_AHRS/AP_AHRS_config.h
index 7338a02787a87..9cfa1715fbec6 100644
--- a/libraries/AP_AHRS/AP_AHRS_config.h
+++ b/libraries/AP_AHRS/AP_AHRS_config.h
@@ -21,11 +21,11 @@
 #endif
 
 #ifndef HAL_NAVEKF3_AVAILABLE
-#define HAL_NAVEKF3_AVAILABLE AP_INERTIALSENSOR_ENABLED
+#define HAL_NAVEKF3_AVAILABLE AP_AHRS_BACKEND_DEFAULT_ENABLED && AP_INERTIALSENSOR_ENABLED
 #endif
 
 #ifndef AP_AHRS_SIM_ENABLED
-#define AP_AHRS_SIM_ENABLED AP_SIM_ENABLED && AP_INERTIALSENSOR_ENABLED
+#define AP_AHRS_SIM_ENABLED AP_AHRS_BACKEND_DEFAULT_ENABLED && AP_SIM_ENABLED && AP_INERTIALSENSOR_ENABLED
 #endif
 
 #ifndef AP_AHRS_POSITION_RESET_ENABLED