Repair Procedures: Inspection

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

Fig 1: Checking Continuity Of Oil Pressure Switch
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 the switch.

Fig 2: Checking Continuity Of Oil Pressure Switch When Fine Wire Is Pushed
Courtesy of KIA MOTORS AMERICA, INC.
If there is no continuity when a 50 kPa (7 psi) is applied through the oil hole the switch is operating properly. Check for air leakage. If air leaks, the diaphragm is broken. Replace it.