diff --git a/workers/lywsd03mmc.py b/workers/lywsd03mmc.py
index 4d2acdf..816ea70 100644
--- a/workers/lywsd03mmc.py
+++ b/workers/lywsd03mmc.py
@@ -29,7 +29,7 @@ def status_update(self):
 
         if self.passive:
             scanner = btle.Scanner()
-            results = scanner.scan(self.scan_timeout or 20.0, passive=True)
+            results = scanner.scan(self.scan_timeout if hasattr(self, 'scan_timeout') else 20.0, passive=True)
 
             for res in results:
                 device = self.find_device(res.addr)