1999 "EE" 90, 115 FFI, 150, 175 V4, V6 FFI Outboards Service Manual, P/N 787024, Page 65Get this manual
System Check TM Engine Monitor
System Check alerts the boat operator to any of four system failuresA dash-mounted gauge and horn combine to warn the driver of potentially damaging engine operating condi tionsThe system is solid-state, water and vibration resistant, with no bulbs to break or burn out2-inch and 3-inch gauges are available2-inch gauges feature four lights only; 3-inch gauges combine the four lights with tachometerSensors on the powerhead and remote oil tank monitor the following conditions:
No Oil Water Temperature
Check Engine Low Oil