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.
Specification
Mazda 6 Service Manual: Dual proportioning valve inspection (without abs)
1. Connect the SSTs to the brake pipes as shown in the figure.
2. Bleed the air from the brake system.
3. Measure the fluid pressure of the master cylinder and the rear brake.
If not within the specification, replace the dual proportioning valve.
Fluid pressure
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Mazda 6 Service Manual: Front door speaker inspection
1. Inspect for resistance between the front door speaker terminals using an
ohmmeter.
If not as specified, replace the front door speaker.
2. To verify that the front door speaker outputs sound, apply voltage to the
front door speaker and release using a 1.5-V battery.
If not outp ...