If there is the possibility of a collision with a vehicle ahead, the beep sounds continuously and a warning is indicated in the multi-information display and the active driving display.

Smart Brake Support (SBS) (Some models)
Stopping The Smart Brake Support (SBS) System OperationMazda 6 Owners Manual: Fuel Gauge (Without Multiinformation Display)
The fuel gauge shows approximately how much fuel is remaining in the tank when
the ignition is switched ON. We recommend keeping the tank over 1/4 full.
If the low fuel warning light illuminates or the fuel level is very low, refuel
as soon as possible.
Refer to Warning Lights.
NOTE
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Mazda 6 Owners Manual: Oil cooler removal/installation
1. Disconnect the negative battery cable.
2. Drain the ATF into a container. (See AUTOMATIC TRANSAXLE FLUID (ATF)
REPLACEMENT.)
3. Remove the radiator. (See RADIATOR REMOVAL/INSTALLATION.)
4. Remove in the order indicated in the table.
5. Install in the reverse order of removal.
6. Add ATF to ...