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: Refrigerant pressure switch inspection
1. Install the SST (gas charging set).
2. Disconnect the refrigerant pressure switch connector.
3. Verify the high-pressure side reading of the SST (manifold gauge)
and continuity between the terminals of the refrigerant pressure switch.
If not as specified, replace the refrigerant pressure ...
Mazda 6 Service Manual: Oil leakage inspection
Use either of the following procedures to identify the type of oil that
is leaking:
Using UV Light (Black Light)
1. Remove on the engine or transaxle.
Note
Referring to the fluorescent dye instruction manual, mix the
specified amount of dye into the engine oil or ATF (or transaxle ...