Ultra sonic Sensor not working correctly

Dear All, I am using Hagisonic HG40DAI sensor with Arduino uno. understand that the PIN 1. Trigger pin 2. Power -5v 3. Echo pin 4. Ground The data sheet is found her (http://www.robotshop.us/content/PDF/hagisonic-anibat-data-sheet.pdf).

Code

#define ECHOPIN  3 // Digital pin 3
#define TRIGPIN  2 // Digital pin 2

void setup() {
  // initialize serial communication:
  Serial.begin(9600);
  pinMode(ECHOPIN,INPUT);
  pinMode(TRIGPIN,OUTPUT);

}

void loop()
{
    digitalWrite(TRIGPIN,LOW);
  delayMicroseconds(2);
  digitalWrite(TRIGPIN,HIGH);
  
   delayMicroseconds(10);
  digitalWrite(TRIGPIN,LOW);
  
   distance =pulseIn(ECHOPIN,HIGH);
   Serial.print(distance); // Distance 1 just checking whether getting  correct distance  here
  distance = distance/58;
   Serial.print(distance);  //Distance 2
  Serial.print(" cm (Distance)");
  Serial.println();
  delay(200);
}

Getting distance 0.00cm at Distance 1 and Distance 2.

Any advise welcome. Appreciate your time and efforts :)

With thanks, Chandra

Read the data sheet. It suggests that the trigger pulse must be more than 2 milliseconds.