Connect battery positive voltage to terminal A and ground to terminal B of the blower motor and verify its operation.

Blower motor removal/installation
Resistor removal/installationMazda 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: STEP 3: Contact Better Business Bureau (BBB)
Mazda North American Operations realizes that mutual agreement on some issues
may not be possible. As a final step to ensure that your concerns are being fairly
considered, Mazda North American Operations has agreed to participate in a dispute
settlement program administered by the Better Busi ...