Concerned with dual battery readings on AR240

[subysti]

OK here is what I've found today. Both batteries charged overnight and charger says they are fully charged. Starting battery is at 12.9VDC and house at 13.4VDC. Not sure why starting battery is at 12.9 but I have a call in to the Prosport people. I'm guessing its either because its new and needs a few charge cycles to accept a full charge or the charger is set to charge the starting battery to this voltage. The leads on the charger are specific to what battery they go to. stupid me though a forgot to check the readings on the conext screen. After a couple hours of running the stereo and couple items the house battery is at 13.2VDC and start is at 12.91. Leap forward a few more hours and the stereo has been running for about 6 hours now and I inflated a couple large towables. The house battery is at 12.2VDC and the start is at 12.9 VDC. hasn't budged. The conext screen says sys battery at 12.2 and aux at 12.2. I check them both again and start is at 12.9. I even started both engines for giggles to see if anything changed on the screen and they both still read 12.2. I'm thinking there is an issue with what is displayed on the conext screen, it seems to only be seeing the house battery. I called Yamaha tech support to see if there was something I was misunderstanding in the way it reads or works on the screen but they had no clue and said I need to bring it in to my dealer. I did check my manual again and on page 45 it states that the sys display should be the starting battery voltage and the aux should be the house battery. If there are any other people seeing this and can verify with a meter what is on their batteries compared to the display there may be an issue with the new boats. I know a couple others have mentioned something similar.

 

[OperationROL]

Great stuff. I will check this weekend. I hope Yamaha can find and fix the issue. Otherwise, the voltage readings are not worth anything and could possibly leave me stranded somewhere.

 

[MikeyL]

[QUOTE="OperationROL, post: 96680, member: 27"]Great stuff. I will check this weekend. I hope Yamaha can find and fix the issue. Otherwise, the voltage readings are not worth anything and could possibly leave me stranded somewhere.[/QUOTE]
I also, and I sincerely thank @subysti for investigating this so thoroughly and "stayin' with it," despite my lack of enthusiasm.
Best Wishes, Mikey Lulejian - Lake Oconee, GA

 

[Edward]

I will check mine within the next few days and let you know what I find.

 

[txav8r]

Just keep in mind that immediately after you charge any battery to full capacity, it has a head charge, that must either be allowed to dissipate or to put a load on it for 5 or 10 minutes, and then check after the load is removed. Otherwise, your only reading head voltage and not actual battery voltage.

 

[subysti]

@txav8r Are you talking about a surface charge? The surface charge would have been removed while using the stereo on the house batt and I also did fire up both engines and the amps needed to start both engines would also remove the surface charge for that batt. The big issue is that the display is not showing the true voltage of both batteries. The starting battery had been sitting for almost 9 hours before I started the engines and even then the voltage didn't move while the house batt went down to 12.2. Both batteries showed 12.2 on the conext display.

 

[txav8r]

Yes, head charge, surface charge, same thing.

 

[MrMoose]

@txav8r Are you talking about a surface charge? The surface charge would have been removed while using the stereo on the house batt and I also did fire up both engines and the amps needed to start both engines would also remove the surface charge for that batt. The big issue is that the display is not showing the true voltage of both batteries. The starting battery had been sitting for almost 9 hours before I started the engines and even then the voltage didn't move while the house batt went down to 12.2. Both batteries showed 12.2 on the conext display.

I wonder what Connext would show if you disconnected one of the leads on your start battery. If both readings are impacted, then something is crossed-up. ??

 

[subysti]

I'm thinking if I disconnect the house battery it will be flaky. It only seems to see the house battery. That's tomorrow's test.

 

[subysti]

Has anyone else checked this out?

 

[Edward]

I checked my batteries tonight. The battery closest to the stern, I'm guessing the start battery, measured 12.6. The other battery, guessing house, measured 12.2 and 12.3. My batteries are not on a charger yet and last time I used the boat was 1 week from this past Sunday. After I measured I flipped the blower on and conext came up and showed 12.0 and 12.1. I then realized that I was incurring load with the blower, shut it off and then key in on. Connext came back up and showed 12.2 and 12.3, not anywhere near my 12.6 for start battery.

Noticed that when I engaged blower both measurements in connext came down. Should that be right? Why would both come down? I would have figured only a draw on one battery.

The data seems to suggest that connext and its sensors are wired incorrectly or the accuracy and degree of variance is off.

I didn't really have a whole lot of time to test more scenarios. I ended up running the blower for about 5 minutes and then cranked up both engines briefly and then shut everything down and tookeasurments again on the batteries and they were pretty much the same.

Anyone else have thoughts or run any tests?

 

[subysti]

Sounds like your getting the same thing as me in that the conext screen is just showing the house battery and not the starting battery.

 

[MrMoose]

I'm thinking if I disconnect the house battery it will be flaky. It only seems to see the house battery. That's tomorrow's test.

Did you try disconnecting the start battery yet? If you think that Connext is only measuring the house battery, then this might be a way to prove your theory.

 

[subysti]

Well I tried but funny thing. nothing powers up if the starting battery is disconnected. So there is some sort of connection to the starting battery. It's not as isolated as we think. I ordered the yamaha service manual. I'm hoping it will have some wiring schematics in it.

 

[Edward]

Well, I do have a "dead" battery in my garage. I could unhook the house and hook up the "dead" one and see what see. I won't be able to get to this until tomorrow after work though...so long as it isn't raining here.

I'd be curious to see what connext says and if it would even power up. Even if I put the dead one as the startup batter, no matter what, the boat should still be able to start if i turn the parallel switch, right?

 

[subysti]

Has anyone else tested this? I'm thinking yamaha may have a wiring issue here.

 

[subysti]

Having the dealer check this out. The screen definitely is wrong. Connected and old battery that was down to 4 volts. Screen still showed 13.1 volts for both which was the the house battery. Also checked the service screen and it showed the same also.

 

[morgro269]

Picking mine up at Congamond tomorrow... I will bring a multimeter see what mine reads....

 

[MrMoose]

Having the dealer check this out. The screen definitely is wrong. Connected and old battery that was down to 4 volts. Screen still showed 13.1 volts for both which was the the house battery. Also checked the service screen and it showed the same also.

Nice job. Thanks for your perseverance and update.

 

[subysti]

I'd like to get some more people to check this out as it seems more like a software issue now.