Water pressur sensor on F150A

We already tried that.. erased the code and it still showed up! we tried reseting the ecu and disconnect the water pressure sensor and the engine worked perfectly and the codes tps and oil pressure sensor stop showing. after plugging it back in the codes show up again and the engine behaves badly again.. any ideas????? shall we replace the water pressure sensor?

That's happened one year ago to Mikrob. Now it happened to me, here in Italy, one week ago, that my F150A (i.e. MY2009, installed on September 2008 along with a FL150A by Pursuit itself on my OS255), stopped itself sending a code 18 (TPS) and, then, a code 39 (oil pressure sensor). It sported also a water-in-fuel alarm, that resulted absolutely false. After many checks and great patience, the official assistance (thanks you!) found the culprit in the water pressure sensor, that was badly damaged, letting the water to pass outside itself (the connectors were completely rusty). I guess that this sensor was added to the F150 family just on MY2009, since it doesn't appear on the previous parts chart, and my mechanic confirmed that.

Waiting for the spare sensor, we remove the good one from the FL150, and closed the related hole with a plug, as in the former model. Everything is running well. The only problem is that, after reset every error codes, the buzzer still emits a low, continuous sound, that, until know, seems impossible to turn off. Waiting for advice from Yamaha Italy, has any of you any idea about that? We tried also to switch ECUs between the two engines, but the alarm still buzzes, so the problem is not in the ECU...

[boats.net]

If you have Command Link gauges then Yamaha has a bulletin for replacement of of water pressure and speed sensors. When the sensor leaks it can result electric harness connections problems and sometimes corrosion problems on connections. Check all connections and grounds.

Thanks a lot, we'll check. But, since we installed the sensor of the twin FL on the faulty engine, and it is working without any error, I should guess that everything is ok (on the mechanic's PC, every value is ok). So, why the buzzer is (lowly) buzzing?

[boats.net]

The warning circuit is partially grounded, check temp and oil pressure sensor and their connections.

Thanks again, I'll check...

[sachin2021]

Mine gave problems. Hard to solve but it was the water pressure sensor. Replaced it and running fine now.