Visual Inspection
Remove the wheel and tire, and inspect the sensor for looseness and damage. Replace the sensor if necessary.
Clearance Inspection
Inspect the clearance between the wheel-speed sensor and the sensor rotor.
Clearance
0.3-1.1 mm {0.012-0.043 in}
Resistance Inspection
1. Disconnect the ABS wheel-speed sensor connector.
2. Inspect the resistance at the ABS wheel-speed sensor.
Resistance
1.3-1.7 kilohm
Voltage Inspection
1. On level ground, jack up the vehicle and support it evenly on safety stands.
2. Disconnect the ABS wheel-speed sensor connector.
3. Inspect each sensor by rotating each wheel one revolution per second.
Voltage
0.25-1.2 V (AC)
Voltage Pattern Inspection
1. On level ground, jack up the vehicle and support it evenly on safety stands.
2. Disconnect the ABS wheel-speed sensor connector.
3. Using an oscilloscope, inspect voltage pattern for distortion and noise by rotating each wheel.
Mazda 6 Service 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 Service Manual: No.4 passenger-side air bag cut-off indicator light is illuminated all the
time
Diagnostic Procedure
When performing an asterisked (*) troubleshooting inspection, shake the
wiring harness and connectors while doing the inspection to discover whether
poor contact points are the cause of any intermittent malfunction. If there
is a problem, check to make sure connec ...