2006 Mercruiser 4.3 oil sensor alarm

[Johnp0505]

Hello,
The water pressure sensor alarm recently started sounding even though no temp issues. I replaced the sensor and now the oil pressure sensor alarm is going off when the engine is started. The oil pressure on the gauge is just above 50 where it usually is. Do I just replace the sensor and if so where is it. Thanks

 

[alldodge]

Is this a MPI? Have a serial number?
You seeing water pressure and oil pressure alarm on vessel view maybe?

 

[Johnp0505]

Yes its an MPI and the serial is OW359281. The alarms are on the Smartcraft display but the gauges are all normal.

 

[alldodge]

Will suggest with key ON, motor not running use a voltmeter on the water pressure switch or oil pressure switch and see if the 5V reference voltage is at 5V. The sensors have 3 wires (5V Ref, Ground, sensor). Reason to measure is to find out if the 5V Ref is being pulled down lower then 5

If it is up to 5V then it just happened that both sensors went bad. If 5V is low, then the oil pressure may be the issue, or could be one of the others like Temp.

The oil switch is on port side of the block down by the oil pan. It will be Tee'd with the oil pressure gauge sender which is large and round and has just one wire attached

 

[Johnp0505]

Thank you. I will try it next week and let you know how I make out.

 

[Johnp0505]

I swapped it out and all is good. Thanks for the help.