I have a 2016 22 VLX, and this past weekend, I started getting a high-voltage warning. (I'll see if I can find the code again.) When the boat is idle, the voltage is fine, but with the throttle engaged, it starts to creep up to around 17.8v on the dash. This happens when on one or both batteries. 

After doing quite a bit of searching, it seems like it's either a bad ground or, most likely, the voltage regulator in the alternator. 

That being said, how hard is it to replace the alternator? Most mechanics in my area are about three weeks out before they can look at it, and it may take an additional week to get the parts. 

Headed out to the boat today with my multimeter to see if I can find the issue. 

Any help is appreciated. 

On an 07, the sensor (gauge reading) should be independent of the actuator movement because it is attached to the starboard pivot bolt for the wedge.  If the battery has been disconnected, you will need to do a calibration which is found in the above links as well. However, if you don’t have any movement down from stored, you need to get your meter out and check for the basics, power at the fuses, power at the wedge actuator connectors on the inside of the transom.

Thanks Csleaver.  Which side is the SPN:441?  I was told port.  Replaced the impeller and still throws the same SPN:441 code.  Also, how do you clean and flush the Manifolds and what can you do about worn sensor connection plug sockets?  Plan to replace the temperature sensors this week.  

Really appreciate the help.  Trying to do what I can before a 6 hour round trip to the dealer.  Thanks 

No.  Only when I'm moving

They changed out the alternator this morning.  Seemed to have fixed it.  I'll report back tomorrow / WED.