Low/High voltage AUX battery warning - Help please

[Eddie Hania]

Just got my new 2016 Yamaha 242 limited, first time on the water for 50 mins all went 100%

second time about 45 mins into our journey while going at about 20 mph a loud alarm is beeping with Low/High voltage AUX battery . so i fiddle along for a little to figure out how to mute the Da$n thing
then finally i succeed at shutting the sound off
alarm still going (silenced) so we head back to shore on one engine (just in case)

I get my own volt meter and with both engines OFF , I get a reading of 19.9 (house batter) and 20.1 V (start battery) .

the touch screen is showing 10.9 and 10.1 V ! very strange.

batteries are outputting very high voltage for sure seems they have been overcharged, if that is possible at all !

i am guessing that the screen is not capable of displaying any reading higher than 19.9 V so it flicks over to 10V onwards again !!

I know I am all over the place, has anyone encountered this before.?

thank you guys

all alone in New Zealand !!
Even the yamaha dealer here has no clue as the is the first boat in New Zealand and Australia

 

[Speedling]

I would be sure to disconnect the batteries first of all so that no more damage can be done. Take the batteries out of the boat and wear gloves. Maybe even goggles. You don't want the things to rupture and get acid on you!

No idea why it would overcharge. Never heard of it before and wouldn't think it possible!

 

[subysti]

First you need to read the posts about the voltage screen display problems. The screen will only display the aux battery voltage because the factory screwed up. Known issue. As for the 20 volts on one battery but not the other it sounds like a voltage regulator isn't working and over charging. Easiest way to check it would be to take out the 20 volt battery and put in a regular 12 volt and then start the engines again and measure the charge voltage going to the battery. Make sure to rev up the engines and see if the voltage rises and drops with the rpm's. If it just goes to 14 volts then the system is fine and they either put in an overcharged battery to start or maybe put in 20 volt battery. Either way it sounds like the dual battery wiring is incorrect and not charging the 2nd battery. There should be a thin black wire, maybe 18 gauge, going from the charging relay next to your switches to a ground terminal on the starting battery. That tells the relay when to switch over and start charging the aux battery.

 

[Mainah]

Check that the little black wire coming off of the battery switches is hooked up to the negative of one of the batteries. I very highly doubt that the batteries are at 20 VDC unless they are wired in series which would be hard to do with the factory wiring. I find it more likley that something is wrong with the multi meter or the setting it was on.

The little black wire thing is a known issue that will cause exactly what you are describing. The little black wire is something that the dealers need to hook up when they install the batteries but it is frequently missed and not suprising as this is the first of that boat for that dealer. Even though connext displays two readings it is really only reading the house battery and the house battery won't charge without the black dvsr wire being connected.

While not needed to operate the boat but also not a bad idea do a search for the connext battery voltage fix but keep in mind that is secondary to getting the little black wire connected.

 

[Mainah]

Just to clarify my over the internet opinion of the multi meter reading not being correct. The little black box that reads the voltage and sends a computer signal to the display is itself very accurate. Even with the factory wiring issue it still reads the correct house battery voltage. If the multi meter read both batteries at 20 volts that would be a conflicting reading. Couple that with the known black wire issue causing the house battery not to charge and the low voltage alarm to go off in fresh from the dealer boats and that is how I came to my over the internet opinion.

 

[swatski]

@Eddie Hania Welcome to the club!!! Sorry you are having electrical gremlins!

Off topic but it has not been mentioned yet: one thing to keep in mind, the engines are raw water cooled so while running on one engine it is prudent to clamp the cooling water intake hose to the "off" engine. Alternatively, keep the other engine in idle, or go real slow. All that to alleviate any chances of water ingestion through the exhaust. Also advisable to push the "off" engine throttle lever into forward position (to open the gate and prevent pressure build up through intakes).

Glad you found us!

--

 

[subysti]

Ok I misread the posting. If both batteries are around 20 VDC I'm guessing the meter was on the wrong setting and doubling the voltage reading when in fact the batteries are both around 10VDC and giving the low voltage alarm. OR the batteries are installed in series instead of parallel and started out at 24 volts but that doubtful as most of the electrical would not have been very happy at all.

 

[Eddie Hania]

It is amazing how many helpful people are out there I really appreciate all of your replies thank you so much
I will be conducting some heavy testing this weekend and will report back for all to benefit

thanks again

 

[Impeller>Propeller]

Any update. I purchased my 242 in December and noticed the same issue. Haven't been back out since to inspect but would love to know what you found out.

 

[Zeus2013]

I would recommend not to check a battery with a volt meter shortly after turning off the engine. There is surface charge that remains and can give you a higher reading then actual. That being said, 20v appears high even for surface charge. Let the battery rest for 24hrs and check after that.

 

[Mainah]

The OP has not been on for over a month. I still recommend that anyone having voltage alarm issues that has a stock dual battey setup check the little black wire from the dvsr is hooked up to the negative terminal of one of the batteries. This is a known and common issue.

 

[Eddie Hania]

at the end it was a faulty batter , once replaced all is 100% a little disappointing for a brand new boat but still happy it was a simple fix