Sparkfun CCS811 sensor not interfacing with arduino I have sparkfun indoor air quality sensor CCS811 which needs to be interfaced with arduino. I have soldered wires on the sensors and connected with arduino. Have checked the connection with multimeter so that part works. But even using example code on library still I am not getting reading from sensor.

Code:-

#include &lt;Wire.h&gt;

#include "SparkFunCCS811.h" 

#define CCS811_ADDR 0x5B //Default I2C Address
//#define CCS811_ADDR 0x5A //Alternate I2C Address

CCS811 mySensor(CCS811_ADDR);

void setup()
{
  Serial.begin(9600);
  Serial.println("CCS811 Basic Example");

  Wire.begin(); //Inialize I2C Harware

  //It is recommended to check return status on .begin(), but it is not
  //required.
  CCS811Core::status returnCode = mySensor.begin();
  if (returnCode != CCS811Core::SENSOR_SUCCESS)
  {
    Serial.println(".begin() returned with an error.");
    //while (1); //Hang if there was a problem.
  }
}

void loop()
{
  //Check to see if data is ready with .dataAvailable()
  if (mySensor.dataAvailable())
  {
    //If so, have the sensor read and calculate the results.
    //Get them later
    mySensor.readAlgorithmResults();

    Serial.print("CO2[");
    //Returns calculated CO2 reading
    Serial.print(mySensor.getCO2());
    Serial.print("] tVOC[");
    //Returns calculated TVOC reading
    Serial.print(mySensor.getTVOC());
    Serial.print("] millis[");
    //Simply the time since program start
    Serial.print(millis());
    Serial.print("]");
    Serial.println();
  }

  delay(10); //Don't spam the I2C bus
}







Things I tried:-
1) different combination of  A4, A5 pins
2) 0x5A &amp; 0x5B i2c address
3) using wake pin with ground
4) using 3.3 &amp; 5V for powering sensor

What else needs to be done?
The problem was on the soldering part. SDA &amp; 3.3V pin on sensor were slightly in contact. I modified it and started working fine.