Go Direct® Surface Temperature Sensor (GDX-ST)
Specifications and User Guide

-Primary Test: Plug in the sensor and start up the data-collection program. Temperature readings should appear on the main screen of the program. Hold the tip of the sensor to warm it and check that the temperature is changing.

-Calibrate? No.

If the sensor can be turned on when connected by USB but not when disconnected from USB, the battery either needs charging or has reached its end of life and can no longer hold a charge. First, try charging the sensor for several hours. If the sensor still won’t turn on when disconnected from USB, the battery has likely reached its end of life. If you intend to use this sensor wirelessly, the battery will need to be replaced. The rechargeable battery in this sensor is covered by a one year warranty but should last two to five years in typical use.
How do I replace the battery in a Go Direct Wand-Type Sensor?

Go Direct® Temperature Probe (GDX-TMP)
Go Direct® Wide-Range Temperature Probe (GDX-WRT)