diff --git a/EKF/covariance.cpp b/EKF/covariance.cpp
index 08452e09eb..f17ce2e681 100644
--- a/EKF/covariance.cpp
+++ b/EKF/covariance.cpp
@@ -737,7 +737,7 @@ void Ekf::fixCovarianceErrors()
 
 		// record the pass/fail
 		if (!bad_acc_bias) {
-			_fault_status.flags.bad_acc_bias = true;
+			_fault_status.flags.bad_acc_bias = false;
 			_time_acc_bias_check = _time_last_imu;
 		} else {
 			_fault_status.flags.bad_acc_bias = true;
diff --git a/EKF/estimator_interface.cpp b/EKF/estimator_interface.cpp
index 3e3e317f8e..6545edc45b 100644
--- a/EKF/estimator_interface.cpp
+++ b/EKF/estimator_interface.cpp
@@ -435,7 +435,7 @@ bool EstimatorInterface::initialise_interface(uint64_t timestamp)
 	_time_last_range = 0;
 	_time_last_airspeed = 0;
 	_time_last_optflow = 0;
-	memset(&_fault_status.flags, 0, sizeof(_fault_status.flags));
+	_fault_status.value = 0;
 	_time_last_ext_vision = 0;
 	return true;
 }
diff --git a/EKF/gps_checks.cpp b/EKF/gps_checks.cpp
index 9a96a8af40..94478c379c 100644
--- a/EKF/gps_checks.cpp
+++ b/EKF/gps_checks.cpp
@@ -57,11 +57,12 @@
 
 bool Ekf::collect_gps(uint64_t time_usec, struct gps_message *gps)
 {
-	// If we have defined the WGS-84 position of the NED origin, run gps quality checks until they pass, then define the origins WGS-84 position using the last GPS fix
-	if (!_NED_origin_initialised) {
-		// we have good GPS data so can now set the origin's WGS-84 position
-		if (gps_is_good(gps) && !_NED_origin_initialised) {
-			// Set the origin's WGS-84 position to the last gps fix
+	// Run GPS checks whenever the WGS-84 origin is not set or the vehicle is not using GPS
+	// Also run checks if the vehicle is on-ground as the check data can be used by vehicle pre-flight checks
+	if (!_control_status.flags.in_air || !_NED_origin_initialised || !_control_status.flags.gps) {
+		bool gps_checks_pass = gps_is_good(gps);
+		if (!_NED_origin_initialised && gps_checks_pass) {
+			// If we have good GPS data set the origin's WGS-84 position to the last gps fix
 			double lat = gps->lat / 1.0e7;
 			double lon = gps->lon / 1.0e7;
 			map_projection_init_timestamped(&_pos_ref, lat, lon, _time_last_imu);