diff --git a/Rover/AP_Arming.cpp b/Rover/AP_Arming.cpp
index e25e3ea7da9..884051e191d 100644
--- a/Rover/AP_Arming.cpp
+++ b/Rover/AP_Arming.cpp
@@ -157,7 +157,7 @@ bool AP_Arming_Rover::disarm(const AP_Arming::Method method, bool do_disarm_chec
 // check object avoidance has initialised correctly
 bool AP_Arming_Rover::oa_check(bool report)
 {
-    char failure_msg[50];
+    char failure_msg[50] = {};
     if (rover.g2.oa.pre_arm_check(failure_msg, ARRAY_SIZE(failure_msg))) {
         return true;
     }
@@ -205,7 +205,7 @@ bool AP_Arming_Rover::motor_checks(bool report)
     bool ret = rover.g2.motors.pre_arm_check(report);
 
 #if HAL_TORQEEDO_ENABLED
-    char failure_msg[50];
+    char failure_msg[50] = {};
     AP_Torqeedo *torqeedo = AP_Torqeedo::get_singleton();
     if (torqeedo != nullptr) {
         if (!torqeedo->pre_arm_checks(failure_msg, ARRAY_SIZE(failure_msg))) {