diff --git a/ColorlampBase.js b/ColorlampBase.js
index aa9dc47..89ee47c 100644
--- a/ColorlampBase.js
+++ b/ColorlampBase.js
@@ -15,19 +15,19 @@ class HCColorlamp extends HCControlBase {
 	}
 
 	turnOn() {
-		return Promise.reject();
+		return Promise.reject("Not implemented");
 	}
 
 	turnOff() {
-		return Promise.reject();
+		return Promise.reject("Not implemented");
 	}
 
 	toggle() {
-		return Promise.reject();
+		return Promise.reject("Not implemented");
 	}
 
 	changeBrightness(brightness) {
-		return Promise.reject();
+		return Promise.reject("Not implemented");
 	}
 
 	/**
@@ -39,11 +39,11 @@ class HCColorlamp extends HCControlBase {
 	 * @param {Number} color.l Lightness
 	 */
 	changeColor(color) {
-		return Promise.reject();
+		return Promise.reject("Not implemented");
 	}
 
 	setEffect(id) {
-		return Promise.reject();
+		return Promise.reject("Not implemented");
 	}
 }