From The Apple Wiki
The ThermalDOE icon

Not much information exists about ThermalDOE, also known as YThermalDOE. In order to function, it requires the use of special configuration files in the form of plists. Such files are packaged separately from internal restore bundles, and may possibly be found on genuine hardware prototypes. If these files are present on a device, this will give the user the ability to perform ThermalDOE-specific tests. Due to the simplistic GUI, which does not provide much information, it is currently not known what these tests are actually for, but it is speculated that they are battery-related.

Configuration Files

Configuration files exist in the form of plist files. They are supposed to be in the /var/private/logs/ThermalDOE/ directory. If they are not present, the corresponding GUI will not load and an error message will be displayed, notifying the user that they are, in fact, absent. They are also known to be very rare and difficult to obtain.

Currently, there are 4 known types of ThermalDOE configuration files, which most likely perform different tests:

Upon putting these plists into the aforementioned directory, ThermalDOE will no longer display an error message, and instead show buttons to run each test that is in the configs directory. Once run, the application will show the caption "Testing in Progress", along with the "scenario" name and test name. You can cancel these tests by pressing the red "cancel test" button.

Application Contents: