Hi Lee,

Please go to the home page. There is a drop down menu and please select your second pixie timer, then tap the "+"button on the upper right corner, go to Add a Product-> Plant sensor and then select the Garden and complete the following procedures to add the sensor. You will need to press the button 6 times on the back of the sensor to change its mode to Setup mode (light blinking slowly).

Please let us know if it works.

Thanks,

Netro Support