When the ignition is switched ON, the outside temperature is displayed.

NOTE
Under the following conditions, the outside temperature display may differ from the actual outside temperature depending on the surroundings and vehicle conditions:
Changing the Temperature Unit of the Outside Temperature Display
The outside temperature unit can be switched between Celsius and Fahrenheit.
Settings can be changed by operating the center display screen.
NOTE
When the temperature unit indicated in the outside temperature display is changed, the temperature unit indicated in the engine coolant gauge display changes in conjunction with it.
Dashboard Illumination
Cruise Control Set Vehicle Speed Display (Without Multiinformation Display)Mazda 6 Owners Manual: Oil pressure switch removal/installation
Warning
When the transaxle and ATF are hot, they can badly burn. Turn off
the engine and wait untill they are cool before replacing ATF.
1. Disconnect the negative battery cable.
2. Remove the under cover.
3. Disconnect the cord assembly connector.
4. Remove the oil pressure switch.
...
Mazda 6 Owners Manual: Engine Exhaust (Carbon monoxide)
WARNING
Do not drive your vehicle if you smell exhaust gas inside the vehicle:
Engine exhaust gas is dangerous. This gas contains carbon monoxide (CO), which is
colorless, odorless, and poisonous. When inhaled, it can cause loss of consciousness
and death. If you smell exhaust gas inside the ...