diff --git a/EKF/ekf_helper.cpp b/EKF/ekf_helper.cpp
index feac851d91..2a408a63e4 100644
--- a/EKF/ekf_helper.cpp
+++ b/EKF/ekf_helper.cpp
@@ -1799,7 +1799,7 @@ void Ekf::runYawEKFGSF()
 	yawEstimator.update(_imu_sample_delayed, _control_status.flags.in_air, TAS);
 
 	// basic sanity check on GPS velocity data
-	if (_gps_data_ready && _gps_sample_delayed.vacc > FLT_EPSILON && isfinite(_gps_sample_delayed.vel(0)) && isfinite(_gps_sample_delayed.vel(1))) {
+	if (_gps_data_ready && _gps_sample_delayed.vacc > FLT_EPSILON && ISFINITE(_gps_sample_delayed.vel(0)) && ISFINITE(_gps_sample_delayed.vel(1))) {
 		yawEstimator.setVelocity(_gps_sample_delayed.vel.xy(), _gps_sample_delayed.vacc);
 	}
 }