2006-2010 Suzuki DF150 / DF175 4-Stroke Outboards Service Manual, Page 120Get this manual
ENGINE CONTROL SYSTEM
IAC VALVE 1Disconnect connector from IAC valve2Check each coil of IAC valve for resistanceTerminals Between "1" and "2" "3" and "2" "4" and "5" "6" and "5" If out of specification, replace IAC valve3Remove IAC valve from intake manifold(See page 3-69 4Connect connector to IAC valve5When the ignition switch is turned ON and OFF, check that the rotary valve turns to open and returns to closed6If the valve does not turn, check the wiring harness for continuity (between ECM and IAC valve) and connector contact conditionResistance