Random Relay 6 pins / 3 pins works, 3 does'nt. What's wrong?

Projects Programming
8

I didn't take the time to put your random ranges into an array (I couldn't figure it out actually) but you could consider simplifying your code using the (suggested) array...

byte ledPin[6] = {2,3,4,5,6,7};
unsigned long lastMillis[6] = {0};
unsigned long ledDelay[6] = {0};

void setup() 
{
  randomSeed(analogRead(A0));
  for(int i = 0; i < sizeof(ledPin)/sizeof(ledPin[0]); i++)
  {
    pinMode(ledPin[i], OUTPUT);
    digitalWrite(ledPin[i], random(2));
    ledDelay[i] = random(2500);
  }
}

void loop() 
{
  for(int i = 0; i < sizeof(ledPin)/sizeof(ledPin[0]); i++)
  {
    if(millis() - lastMillis[i] > ledDelay[i])
    {
      digitalWrite(ledPin[i], !digitalRead(ledPin[i])); //edit added the not
      lastMillis[i] = millis();
      ledDelay[i] = random(2500);
    }
  }
}

compiles but not tested