Oil alarm only over 2500 89 100HP

[ExxWhy]

We got an intermittent alarm tone yesterday, I believe that is low oil alarm. Only goes off above 2500 RPM. Motor is a 1989 100 Merc, serial OB300685.

Searched through several threads, but not sure if this model only has a low oil in the tank alarm only or if it also has other sensors in the system. Seems like it will be difficult/impossible to troubleshoot it using the "disconnect the brown wire and see if the alarm stops" method without being on the water.

Any sage advice on where to start on dry land?

 

[Dave1027]

Re: Oil alarm only over 2500 89 100HP

Intermittent beep is the low oil alarm. The engine schematic does not show anything about a sensor for the oil drive. It can onlybe two things. The oil tank sensor or the module. Disconnect a blue wire fron the tank and try it. If it's still goes off then the module is bad. If not then it's the tank sensor.

 

[ExxWhy]

Re: Oil alarm only over 2500 89 100HP

Thank you. Checked the Seloc manual and it showed just the oil level sensor, but wasn't 100% confident that was the correct diagram. Thought it was odd it only does it above 2500, but seems to be a false alarm either way.