Oil Pressure Sensor Assembly

Check the continuity between the terminal and the body with an ohmmeter. If there is no continuity, replace the oil pressure switch.

Fig 1: Testing Oil Pressure Sensor Assembly (1 Of 2)
Courtesy of KIA MOTORS AMERICA, INC.
Check the continuity between the terminal and the body when the fine wire is pushed. If there is continuity even when the fine wire is pushed, replace sensor.

Fig 2: Testing Oil Pressure Sensor Assembly (2 Of 2)
Courtesy of KIA MOTORS AMERICA, INC.
Or, if there is no continuity when a 50 kPa (7 psi) vacuum is applied through the oil hole, the switch is operating properly.
Check that air doesn't leak. If air leaks, the diaphragm is broken. Replace the sensor.