Start battery low voltage alarm

[Michael Barone]

Hello. I am new to this forum and a new Yamaha boat owner. We have a 2018 242 Limited S E-Series. We are having an issue with the batteries. When docked, we try to turn the start battery off and the house battery on. This causes a "low voltage" alarm to display for the start battery. The only workaround we have found so far is to leave the key in the ignition. We have pulled the kill switch lanyard; however, we would obviously like to not have to leave the key in the boat, let alone the ignition, when we are not on it. Has anyone else had this issue, and do you know how to fix it? Thank you in advance for the help.

 

[Mainah]

Welcome. What is the purpose for leaving the house battery on when docked? There is no way to defeat the low voltage alarm and also get an accurate voltage reading for the start battery when needed. I can say for my 2016 I have shore power and still shut both batteries off. I did install a dedicated float bilge direct wired to the batteries but a second bilge is a good thing.

 

[Kahuna Khris]

I leave my house battery on at the slip as well to keep the bilge powered in case of rain. My "low voltage"alarm has been going off recently and was due to a bad starting battery. The alarm disappeared if I turned on the parallel battery isolation switch so that both the house and start batteries were connected. My boat is 2016 so I'm not that surprised I have lost at least one battery, but will be replacing both.
Even though your boat is new it could still have a bad battery. Easiest to check so I would start there. Good luck.