diff --git a/src/main.cpp b/src/main.cpp
index c68e961..974114b 100644
--- a/src/main.cpp
+++ b/src/main.cpp
@@ -1,19 +1,18 @@
 #include <Arduino.h>
 
-#define RELAY 2 // GPIO4
-#define LED 5   // GPIO5
+#define RELAY 4 // GPIO4
 
 void setup() {
   Serial.begin(9600);
-  pinMode(LED, OUTPUT);
+  pinMode(LED_BUILTIN, OUTPUT);
   pinMode(RELAY, OUTPUT);
 }
 
 void loop() {
-  digitalWrite(LED, HIGH);
+  digitalWrite(LED_BUILTIN, HIGH);
   digitalWrite(RELAY, HIGH);
   delay(1000);
-  digitalWrite(LED, LOW);
+  digitalWrite(LED_BUILTIN, LOW);
   digitalWrite(RELAY, LOW);
   delay(1000);
 }