diff --git a/libraries/AP_RangeFinder/AP_RangeFinder_PulsedLightLRF.cpp b/libraries/AP_RangeFinder/AP_RangeFinder_PulsedLightLRF.cpp
index 5ceb1925c0..dbb4ace8aa 100644
--- a/libraries/AP_RangeFinder/AP_RangeFinder_PulsedLightLRF.cpp
+++ b/libraries/AP_RangeFinder/AP_RangeFinder_PulsedLightLRF.cpp
@@ -207,7 +207,7 @@ bool AP_RangeFinder_PulsedLightLRF::init(void)
         }
     }
 
-    printf("Found LidarLite device=0x%x v2=%d v3hp=%d\n", _dev->get_bus_id(), (int)v2_hardware, (int)v3hp_hardware);
+    printf("Found LidarLite device=0x%x v2=%d v3hp=%d\n", unsigned(_dev->get_bus_id()), (int)v2_hardware, (int)v3hp_hardware);
     
     _dev->get_semaphore()->give();
 
diff --git a/libraries/AP_RangeFinder/AP_RangeFinder_VL53L0X.cpp b/libraries/AP_RangeFinder/AP_RangeFinder_VL53L0X.cpp
index a5f32ce06b..2286532cc3 100644
--- a/libraries/AP_RangeFinder/AP_RangeFinder_VL53L0X.cpp
+++ b/libraries/AP_RangeFinder/AP_RangeFinder_VL53L0X.cpp
@@ -259,7 +259,7 @@ bool AP_RangeFinder_VL53L0X::check_id(void)
         v2 != 0xAA) {
         return false;
     }
-    printf("Detected VL53L0X on bus 0x%x\n", dev->get_bus_id());
+    printf("Detected VL53L0X on bus 0x%x\n", unsigned(dev->get_bus_id()));
     return true;
 }
 
diff --git a/libraries/AP_RangeFinder/AP_RangeFinder_VL53L1X.cpp b/libraries/AP_RangeFinder/AP_RangeFinder_VL53L1X.cpp
index c444546239..97e778eb70 100644
--- a/libraries/AP_RangeFinder/AP_RangeFinder_VL53L1X.cpp
+++ b/libraries/AP_RangeFinder/AP_RangeFinder_VL53L1X.cpp
@@ -81,7 +81,7 @@ bool AP_RangeFinder_VL53L1X::check_id(void)
         (v2 != 0xCC)) {
         return false;
     }
-    printf("Detected VL53L1X on bus 0x%x\n", dev->get_bus_id());
+    printf("Detected VL53L1X on bus 0x%x\n", unsigned(dev->get_bus_id()));
     return true;
 }