2004 SR Johnson 2-stroke 40, 50HP Service Manual, Page 90Get this manual
ELECTRICAL SYSTEM CHECK CIRCUIT TESTS If battery voltage is present at the purple wire and the tanblue wire has continuity between the two connectors, replace System Check gaugeTurn the key switch ONAfter the normal self-test sequence, the gauge WATER TEMPHOT indicator should stay on If LED is not on, test circuit for continuityTest for continuity of both the engine harness (tan black or tanblue wire) and the MWS instrument harness (tan wire)Turn the key switch OFF and connect all disconnected circuits
IMPORTANT: To test the temperature switch itself, refer to WATER TEMPERATURE SWITCH TEST on p99
LOW OIL Circuit Test
Remove the four screws retaining the pickup assembly to the oil tankTurn the key switch ONLift the pickup assembly out of the tank and hold it uprightAs the float drops, the LOW OIL light should turn on after 40 seconds12Purple wire Tanblue wire