diff --git a/src/ds18b20/ds18b20.c b/src/ds18b20/ds18b20.c
index 11eb06d4..bfee586c 100644
--- a/src/ds18b20/ds18b20.c
+++ b/src/ds18b20/ds18b20.c
@@ -144,7 +144,7 @@ ds18b20_context ds18b20_init(unsigned int uart)
       rv = mraa_uart_ow_rom_search(dev->ow, 0, id);
     }
 
-  if (!dev->numDevices)
+  if (!dev->numDevices || !dev->devices)
     {
       printf("%s: no DS18B20 devices found on bus\n", __FUNCTION__);
       ds18b20_close(dev);