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Dual H-Bridge Motor Driver - L298N not given enough power to motors Answered

Hi there, am very new to the electronics community, I recent bought my first arduino. I wanted to build me own RC car, so I bought Dual H-Bridge Motor Driver L298N Module from ebay (http://www.ebay.co.uk/itm/Dual-H-Bridge-Motor-Driver-L298N-Module-For-Arduino-PIC-DC-Stepper-L298-Board-/251291436187?pt=UK_BOI_Industrial_Automation_Control_ET&hash=item3a8223049b)

I think I have connected everything correctly but somehow the 2 dc motors connected to the motor driver don't seem to move, I have tried a 9v battery to power the motor shield but doesn't seem to do anything. I  used this diagram do the connection to the arduino http://i.imgur.com/JCBcSfL.jpg
The arduino itself has it own 9v battery powering it. I have checked both motors and they work fine. when i switch on the rc car the led on the motor shield blinks but the motors just don't move. I used a digital multimeter to measure the voltage going into the motor. it goes upto 0.36v  then drops. does that mean there isn't enough voltage going into the motors? and how much voltage do you recommend to get it working?

Images of the rc car

The code am running on the arduino

//motor A
int dir1PinA = 2;
int dir2PinA = 3;
int speedPinA = 9;

//motor B
int dir1PinB = 4;
int dir2PinB = 5;
int speedPinB = 10;

unsigned long time;
int speed;
int dir;

void setup(){
time = millis();
speed = 0;
dir = 1;


void loop(){
  analogWrite(speedPinA, speed);
  analogWrite(speedPinB,255 - speed);
  //set direction
  if(1 == dir){
    digitalWrite(dir1PinA, LOW);
    digitalWrite(dir2PinA, HIGH);
    digitalWrite(dir1PinB, HIGH);
    digitalWrite(dir2PinB, LOW);
    digitalWrite(dir1PinA, HIGH);
    digitalWrite(dir2PinA, LOW);
    digitalWrite(dir1PinB, LOW);
    digitalWrite(dir2PinB, HIGH);
  if(millis() - time > 5000){
    time = millis();
    speed += 20;
    if(speed > 255){
      speed = 0;
    if(1 == dir){
      dir = 0;
      dir = 1;


me too bro i have the same issue


4 years ago

Did you make a COMMON GROUND for both the Arduino Board and the Motor Shield? If yes, then the 9V battery is just the case..
Replace the battery with sort of a bit high current capacity battery e.g Lithium Ion Cell or Lithium Polymer cell as these have good discharge capacity to withstand the motor current.
Best of Luck!

What does it mean to have a common ground?

Is there an existing circuit diagram? Hard to give an answer without all the details.

Amerage is the current needed to run the motors which is not the same as voltage. Check the specs on your motors to see how many total milliamps or amps they might draw. You might need a whole pack of AA, C or D batteries wired to give 9 volts but would have the oomph to make the motors move. Good luck.