2004 SR Johnson 2-stroke 40, 50HP Service Manual, Page 89Get this manual
ELECTRICAL SYSTEM CHECK CIRCUIT TESTS
SYSTEM CHECK CIRCUIT TESTS
Make sure the System Check engine monitor can alert the operator during "NO OIL," "WATER TEMP" or "HOT," "CHECK ENGINE," or "LOW OIL" conditionCheck the condition of the warning system and associated wiring and connectionsTest the engine monitor regularly and anytime you suspect an alert situation has been missedThe instrument harness must be connected to the outboard before performing the following testsRefer to the Engine Wiring diagram and the MWS Instrument Wiring diagram in the back of this manual
If the gauge lights do not turn on, turn the key switch OFFDisconnect the gauge a-pin connector from the back of the gauge and turn the key switch ON Test for battery voltage between instrument harness terminal (purple wire) and terminal (black wire)
1Test adapter(s) 2Connector, System Check gauge
IMPORTANT: Use jumper wires made with the appropriate terminals to test the warning circuits