8 Relay module NOT WORKING

8 relay module not working on Arduino Mega and Uno but on Raspberry pi works without problems :(( Any ideas what could be wrong? I tried with external power, different codes and nothing.. While on raspberry pi it works only with USB power :( Thanks

Perhaps if you provided some details, people might be able to help.

Hey, thanks for reply.. I have provided all info because my problem is very basic... Wired similar like image below, used this code and nothing happened... i thought it was module problem so i ask friend to try with his Raspberry and it worked.

#define RELAY1  6                        

#define RELAY2  7                        

#define RELAY3  8                        

#define RELAY4  9



void setup()

{    

// Initialise the Arduino data pins for OUTPUT

  pinMode(RELAY1, OUTPUT);       

  pinMode(RELAY2, OUTPUT);

  pinMode(RELAY3, OUTPUT);

  pinMode(RELAY4, OUTPUT);

}



 void loop()

{

   digitalWrite(RELAY1,LOW);         

   delay(100);                                      

   digitalWrite(RELAY1,HIGH);         



   digitalWrite(RELAY2,LOW);          

   delay(100);                                     

   digitalWrite(RELAY2,HIGH);          



   digitalWrite(RELAY3,LOW);         

   delay(100);                                   

   digitalWrite(RELAY3,HIGH);          



   digitalWrite(RELAY4,LOW);           

   delay(100);                                    

   digitalWrite(RELAY4,HIGH);        

 }

My module have 8 relays this image is only for demonstration purposes. |486x500

SOLVED***

it needs to be plugged on 12v

…but still not clear how the hell it worked with Raspberry ONLY with USB power… perhaps some current limitations…