A reading of -1767.8F signifies that the thermistor wires have broken or the battery has not been fully inserted causing a short between the thermistor leads on the sensor board. If this happens; try removing the battery, wait 60 seconds then re-insert the battery making sure to push the battery all the way to the back of the sensor housing. When the sensor comes back online check the reading to see if it has been corrected. If the problem persists you will need to contact ProTAACS customer support for more information.