diff --git a/src/newgrf_engine.cpp b/src/newgrf_engine.cpp
--- a/src/newgrf_engine.cpp
+++ b/src/newgrf_engine.cpp
@@ -946,7 +946,7 @@ static uint32 VehicleGetVariable(Vehicle
 		default: break;
 	}
 
-	DEBUG(grf, 1, "Unhandled vehicle variable 0x%X, type 0x%X", variable, (uint)v->type);
+	Debug(grf, 1, "Unhandled vehicle variable 0x{:X}, type 0x{:X}", variable, (uint)v->type);
 
 	*available = false;
 	return UINT_MAX;