diff --git a/ArduSub/AP_Arming_Sub.cpp b/ArduSub/AP_Arming_Sub.cpp
index 0fa4f07803..39bebb4a1b 100644
--- a/ArduSub/AP_Arming_Sub.cpp
+++ b/ArduSub/AP_Arming_Sub.cpp
@@ -31,7 +31,7 @@ bool AP_Arming_Sub::ins_checks(bool display_failure)
     // additional sub-specific checks
     if ((checks_to_perform & ARMING_CHECK_ALL) ||
         (checks_to_perform & ARMING_CHECK_INS)) {
-        if (!AP::ahrs().healthy()) {
+        if (!AP::ahrs().prearm_healthy()) {
             const char *reason = AP::ahrs().prearm_failure_reason();
             if (reason == nullptr) {
                 reason = "AHRS not healthy";