The light illuminates continuously when the engine coolant temperature is low and turns off after the engine is warm.
Mazda 6 Owners Manual: Disconnection of the negative battery cable
Before beginning any work, turn the ignition switch to LOCK position,
then disconnect the negative battery cable and wait for more than 1 minute
to allow the backup power supply of the SAS unit to deplete its stored
power. Disconnecting the battery cable will delete the memories of the
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Mazda 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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