A small number of LabQuest 2 units shipped in the Fall of 2016 that have an improper internal calibration. These LabQuests read certain sensors poorly. The most common symptom is that the LabQuest 2 will read a number around 80C at room temperature when any of the following sensors are attached:
Stainless Steel Temperature Probe, order code TMP-BTA, $29
Surface Temperature Sensor, order code STS-BTA, $23
Other sensors that give bad readings include:
Voltage Probe, order code VP-BTA, $12 (reads -10V when the leads are connected to each other
30-Volt Voltage Probe, order code 30V-BTA, $49 (reads -30V when the leads are connected to each other.)
Other analog sensors may read slightly off on these LabQuest 2 units, but probably not by enough that you would immediately notice. The best way to positively diagnose that the issue isn't just a defective sensor is to try the same sensor on other interfaces.
This is not fixable in the field. LabQuest 2 units with this issue need to come to Vernier for recalibration. Contact Tech Support to arrange an RMA.