Mercury Optimax Models 135, 150, Direct Fuel Injection., Page 132Get this manual
WIRING DIAGRAMS
Warning System Signals
NOTE: The warning system signals which includes audible and visual indicator involving the horn and lights will identify the potential problems listed in the chart
Problem Horn Check Engine Light Low Oil Light Over Heat Light Water In Fuel Light Engine Speed Reduction Activated (approx3000 RPM) No No
Power UpSystem Check Low Oil
Single Beep Beep2 Minutes Off Continuous Beep
No Oil Flow