Outside Temperature Display: Description and Operation
EXTERNAL TEMPERATURE DISPLAYWhen the ignition is first turned ON, the external temperature displayed will be the last temperature read before the ignition was turned OFF. If the last temperature read is below 6°C (43°F), the HVAC module - EATC or HVAC module - DATC will prevent A/C operation.
The external temperature display will update when the vehicle has been driven above 40 km/h (25 mph) for greater than 30 seconds. Once the DATC/EATC module updates the external temperature, the HVAC module - EATC or HVAC module - DATC will allow normal A/C operation.
External Temperature Display
The external temperature is displayed when the EXT button is pressed. While the actual external temperature can vary continuously, the value that is displayed will update at a specific rate depending on whether or not the engine is "hot" and whether or not the vehicle is moving.
When the external temperature is rising, the display will update slowly.
Updates (when the actual external temperature is higher than currently displayed value) will be limited to 0.6°C (1°F) every 20 seconds while the vehicle is moving at greater than 40 kph (25 mph) for more than 90 seconds OR 0.6°C (1°F) every 20 minutes if the vehicle is not moving at this speed. This is to prevent the heat from the engine compartment from affecting the accuracy of the display.
When the external temperature is dropping, the display will update quickly.
Updates (when the actual external temperature is lower than currently displayed value) will only be limited to 0.6°C (1°F) every 2 seconds (regardless of vehicle speed). Consequently the display will essentially follow the drop experienced by the external temperature thermistor.