2006 Johnson SD 30 HP 4 Stroke Outboards Service Manual, PN 5006592, Page 79Get this manual
ENGINE CONTROL CAUTION SYSTEMS
CAUTION SYSTEMS
There are three caution systems that alert the operator when an abnormality occurs on the engine: Over-revolution caution system Low oil pressure caution system Overheat caution system caution lamp will be illuminated when an abnormality occurs and the appropriate caution system is activatedOn remote control models, buzzer will also sound for low oil pressure or overheat cautionTo check the caution lamp (and the buzzer, on remote control models), start the engineTwo seconds after starting, the caution lamp should come on (and, on remote control models, the buzzer should sound)