Suzuki DF200/DF225/DF250 V6 4-Stroke Outboards Service Manual, Page 123Get this manual
ENGINE CONTROL SYSTEM
OIL PRESSURE SWITCH NOTE: Before checking the oil pressure switch, make sure the engine oil pressure is within specification1Remove the blue lead wire from oil pressure switch2Check the continuity between the switch terminal and engine body ground" 09930-99320: Digital testerTester range: ( (Continuity) Engine running Engine stopped Infinity Continuity
1 1Oil pressure switch
If measurement exceeds specification, replace oil pressure switch3Reinstall parts removed earlier