1998 Ford Ranger

OIL PRESSURE GAUGE TEST
Disconnect oil pressure sensor harness connector. Connect instrument gauge system tester to oil pressure sensor harness connector wire. Turn ignition on. Set tester to infinity. Oil pressure gauge should read below "L" (low). Short oil pressure sensor harness connector wire to ground. Oil pressure gauge should read above mid scale. If oil pressure gauge functions as specified, replace oil pressure switch. If oil pressure gauge does not function as specified, replace oil pressure gauge.