The fourth test screen, which is visible if your console is equipped with HVAC equipment, shows the results of the temperature self-test, which is performed automatically by the Self Diagnostics Utility every 90 days on any installed heater, air conditioner (A/C), or both.
When this test runs, the utility checks that an installed heater is able to raise the temperature of the battery bay by a specified number of degrees from the bay’s temperature at the time the test initiates. It makes a similar check on the A/C’s ability to lower the temperature.
The results of the temperature self-test, along with a note about how many days have passed since it was performed, is shown on this screen. A passed self-test, for heater or A/C, is shown by a check mark (Fig. A); a failed self-test is shown by an X (Fig. B). The screen will only show a result for a heater or A/C if it is present. After viewing the result, press ENTER to proceed to the next test.
Further explanation of why this test is performed is available by pressing [HH]. Note that a failed self-test is also indicated by a RED HH lamp (Fig. C).