Move the float to the topmost and bottommost positions, and verify that the resistance between terminals A and B of the unit and the position of the float are as indicated in the figure.

Pid/data monitor and record procedure
Oil pressure switch inspectionMazda 6 Service Manual: Dual proportioning valve replacement (without abs)
1. Remove in the order indicated in the table.
2. Install in the reverse order of removal.
Dual Proportioning Valve Installation Note
Install the dual proportioning valve so that the R mark faces the left side
of the vehicle.
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Mazda 6 Service Manual: Combination switch removal/installation
1. Disconnect the negative battery cable.
2. Remove the driver-side air bag module. (See DRIVER-SIDE AIR BAG MODULE
REMOVAL/INSTALLATION.)
3. Remove the steering wheel. (See STEERING WHEEL AND COLUMN
REMOVAL/INSTALLATION.)
4. Remove the column cover. (See COLUMN COVER REMOVAL/INSTALLATION)
5 ...