Remove and install the PCM. (See PCM REMOVAL/INSTALLATION.)
Mazda 6 Service 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 Service Manual: Radar Sensor (Front) (Some models)
Your vehicle is equipped with a radar sensor (front).
The following systems also use the radar sensor (front).
Distance Recognition Support System (DRSS)
Mazda Radar Cruise Control (MRCC)
Smart Brake Support (SBS)
The radar sensor (front) functions by detecting the radio waves reflected ...