diff --git a/modules/@amperka/led.js b/modules/@amperka/led.js
index 1f4f76b..cf8cd6b 100644
--- a/modules/@amperka/led.js
+++ b/modules/@amperka/led.js
@@ -87,7 +87,7 @@ Led.prototype.blink = function(onTime, offTime) {
 };
 
 Led.prototype.brightness = function(value) {
-  if (arguments.length === 0) {
+  if (typeof value === 'undefined') {
     return this._brightness;
   }