diff --git a/model_device.go b/model_device.go
index 3f497b0a6..1882e7fd2 100644
--- a/model_device.go
+++ b/model_device.go
@@ -1962,13 +1962,13 @@ func (o *Device) UnmarshalJSON(data []byte) (err error) {
 	}
 
 	for _, requiredProperty := range requiredProperties {
-		if value, exists := allProperties[requiredProperty]; !exists || value == "" {
+		if _, exists := allProperties[requiredProperty]; !exists {
 			if _, ok := defaultValueFuncMap[requiredProperty]; ok {
 				allProperties[requiredProperty] = defaultValueFuncMap[requiredProperty]()
 				defaultValueApplied = true
 			}
 		}
-		if value, exists := allProperties[requiredProperty]; !exists || value == "" {
+		if _, exists := allProperties[requiredProperty]; !exists {
 			return fmt.Errorf("no value given for required property %v", requiredProperty)
 		}
 	}