Inspecting Brake/Clutch Fluid Level
WARNING
If the brake/clutch fluid level is low, have the brakes inspected:
A low brake/clutch fluid level is dangerous. A low level could indicate brake lining wear or a brake system leak which could cause the brakes to fail and lead to an accident.
The brakes and clutch draw fluid from the same reservoir.
Inspect the fluid level in the reservoir regularly. It should be kept between the MAX and MIN lines.
The level normally drops with accumulated distance, a condition associated with wear of brake and clutch linings. If it is excessively low, have the brake/clutch system inspected by an Authorized Mazda Dealer.

Inspecting Coolant Level
Washer FluidMazda 6 Owners Manual: Pcv valve inspection
1. Disconnect the negative battery cable.
2. Remove the intake maniforld.(see INTAKE-AIR SYSTEM REMOVAL/INSTALLATION.)
3. Remove the PCV valve.
4. Blow through the valve and verify that air flows as specified.
If not as specified, replace the PCV valve.
Specification
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Mazda 6 Owners Manual: Heated oxygen sensor (ho2s) inspection
HO2S Voltage Inspection
Note
Perform the following inspection only when directed.
1. Warm up the engine and run it at idle.
2. Disconnect the HO2S connector.
3. Connect the voltmeter test leads to the following HO2S terminals:
HO2S (front and rear)
- (+) leadterminal A
- (-) le ...