Fix for Connext Battery Voltage Issue - Confirmed

[Bluewater272]

I used 14ga wire. Not for any particular reason, but had some leftover from another project.

 

[JDRacing]

The current draw on that sensing wire is so small, and the run is so short, you could easily use smaller wire (like 16 or 18 gauge) and it wouldn't make a difference. But if I recall correctly, I used some leftover 14 gauge wire, simply because it looked about the same size as the one I cut, and because the leftover wire was red.

Jeff

 

[Leendert]

Guys thanks for this Thread. I have a 2017 242X and I just changed the lead from C terminal to A terminal. Will swap later at SPU as the AUX is now the Start Battery. Nut on the terminal is 11/17.

 

[Augieol65]

Thank you so much for this. I believe this was the last bit of info I needed to figure out how to add into the connext system to add docking lights, tower lights buttons onto my system that doesn’t have those currently available (212 LTS). Once I get the boat out of storage and prove it works I’ll write it up.

 

[FLJetBoater]

Yamaha is in denial about that issue, I would not count on any help, unfortunately.
I think that fixing it in a E-series boat is kind of important. The reason is, having an AUX battery issue will disable a boat with e-throttles, but you may not know what predicament without @Mainah fix.

--

Digging up an old thread here but have been researching some battery threads for an issue I’m having. Interestingly enough in my 2020 242SE I can run the boat just fine with only the start battery turned on and house/parallel off. Is it possible the throttle sensors are powered from the start battery?

 

[Orso]

Thank you for this fix. This is a great way to keep track of the true voltages on my batteries. This is especially important now that I've wired my ballast pumps to be able to work without the engines (s) on.

 

[FSH 210 Sport]

No it will not. It's only affecting how the batteries are displayed on the connext display. As long as you don't mess with the Perc switch, when engines are running the stators will charge the starting bank first then house bank.

Recently I discovered that the DVSR does not look at the start and house batteries separately, the DVSR looks at the both the start and house batteries for its close voltage signal of 13.4VDC. In other words, if the DVSR detects what it thinks is charging voltage the relay will close the positive contact and parallel the start and house batteries.

The start battery cables are connected to the engines, so by virtue of how the engine battery cables are connected to the start battery means the start battery charges first since it is connected to the charging system, thereby raising the voltage the DVSR sees to 13.4VDC, then the relay closes the contact paralleling the start and house batteries.



I discovered this when I upgraded my house battery to a Battle Born 100AhLiFePO, the resting voltage of a fully charged LiFePO battery is 13.6VDC. When I connected the LiFePO battery the DVSR closed and started “charging” the AGM start battery. I had to cut the red wire on the back of the DVSR and hooked it up to a switched ckt so that the operating power source for the DVSR is now manually controlled. After starting main engines I wait for the AGM start battery to either be equal to or greater than the house LiFePO battery then switch on the operating power to the DVSR for it to parallel the batteries, then turn the switch off when I stop. In the near future the DVSR operating power will get its source / operating power via an ignition hot that passes through a time delay relay with a 300 second delay to allow the voltage on the AGM start battery voltage to be > or = to the LiFePO house battery before paralleling so that the electron flow will be towards the house battery.


The issue I have with the connext battery voltages is that they read .4 volts low on both batteries. The battery levels do change, ergo the house battery voltage (in the past with a flooded acid battery) will drop well below the start battery after many hours on the water with the fish finder and live well running while the start battery voltage is stable.

So it appears that the issue with the SPU having continuity may have been solved on my 2020 model year boat.

My question is, what is causing both batteries to read low by .4 volts respectively on the connext screen @Mainah ? My friend suggested it might be a zener diode used in the system that is causing this, could it be a zener diode in the SPU?

I had thought initially that my 30 year old Fluke 77 meters’ calibration may have drifted a bit, but I took it to an electronics store and checked it against one of the stores meters and against my friends much younger Fluke meter and my meter was spot on with those meters.

 

[212s]

My question is, what is causing both batteries to read low by .4 volts respectively on the connext screen

I'll have to put my meter on my batteries tonight to see what they read directly because I don't think my system shows low voltage. My Connext shows what appears to be correct resting and charging voltages at 12.7 and 14.4 volts, rising and falling as they're being charged or used while floating. When charging and near full, do you get 14.4v or is it 14.0v at the Connext?

 

[212s]

My question is, what is causing both batteries to read low by .4 volts

Just checked my batteries with DVM and they're reading +0.03v compared to the Connext screen which is negligible and likely due to longer wire resistance. Perhaps the difference is a software config with the Connext screen? When was your boat made - mine was Feb 2020.

 

[FSH 210 Sport]

I'll have to put my meter on my batteries tonight to see what they read directly because I don't think my system shows low voltage. My Connext shows what appears to be correct resting and charging voltages at 12.7 and 14.4 volts, rising and falling as they're being charged or used while floating. When charging and near full, do you get 14.4v or is it 14.0v at the Connext?

While underway, and after the batteries are mostly charged I see between 14.3-14.4, but I’ve not checked the voltage with my Fluke meter at that point.

 

[FSH 210 Sport]

Just checked my batteries with DVM and they're reading +0.03v compared to the Connext screen which is negligible and likely due to longer wire resistance. Perhaps the difference is a software config with the Connext screen? When was your boat made - mine was Feb 2020.

Im not exactly sure of the build date but I’m guessing it was late 2019 or early 2020 as I saw the boat online at the dealership as early as late February of 2020.

Thanks a lot for going out and checking voltages for me!

 

[Mainah]

Recently I discovered that the DVSR does not look at the start and house batteries separately, the DVSR looks at the both the start and house batteries for its close voltage signal of 13.4VDC. In other words, if the DVSR detects what it thinks is charging voltage the relay will close the positive contact and parallel the start and house batteries.

The start battery cables are connected to the engines, so by virtue of how the engine battery cables are connected to the start battery means the start battery charges first since it is connected to the charging system, thereby raising the voltage the DVSR sees to 13.4VDC, then the relay closes the contact paralleling the start and house batteries.

View attachment 177158

I discovered this when I upgraded my house battery to a Battle Born 100AhLiFePO, the resting voltage of a fully charged LiFePO battery is 13.6VDC. When I connected the LiFePO battery the DVSR closed and started “charging” the AGM start battery. I had to cut the red wire on the back of the DVSR and hooked it up to a switched ckt so that the operating power source for the DVSR is now manually controlled. After starting main engines I wait for the AGM start battery to either be equal to or greater than the house LiFePO battery then switch on the operating power to the DVSR for it to parallel the batteries, then turn the switch off when I stop. In the near future the DVSR operating power will get its source / operating power via an ignition hot that passes through a time delay relay with a 300 second delay to allow the voltage on the AGM start battery voltage to be > or = to the LiFePO house battery before paralleling so that the electron flow will be towards the house battery.


The issue I have with the connext battery voltages is that they read .4 volts low on both batteries. The battery levels do change, ergo the house battery voltage (in the past with a flooded acid battery) will drop well below the start battery after many hours on the water with the fish finder and live well running while the start battery voltage is stable.

So it appears that the issue with the SPU having continuity may have been solved on my 2020 model year boat.

My question is, what is causing both batteries to read low by .4 volts respectively on the connext screen @Mainah ? My friend suggested it might be a zener diode used in the system that is causing this, could it be a zener diode in the SPU?

I had thought initially that my 30 year old Fluke 77 meters’ calibration may have drifted a bit, but I took it to an electronics store and checked it against one of the stores meters and against my friends much younger Fluke meter and my meter was spot on with those meters.

My set up is much different now. Running two group 31 agms as a single bank full time (jump pack for emergencies). Connext displays one tenth off between start and house at times even though both leads connected to the same bank. Lots of things could cause this from board density to thickness of printed paths. Connext differs around a tenth from my DMM as I recall. The SPU houses the electronics that “read” the volatge then parses that as data over canbus to the connext screen. Keep in mind different types and sizes of batteries will have different float voltages

My decision to go single bank better supports the high loads I have at times. I made the swap when I replaced the factory main power harness to the starters and ecus with 0 awg. No more infrequent Connext errors on startup due to starter induced voltage drop with the much smaller factory harness.
My current set up looks like the below with both batteries going to the set of busbars. Busbars go to the battery switches, voltage leads for the SPU, single bank battery charger, and second bilge that is on a float switch. Battery switches go the the main power harness and the run behind the helm for all of the loud stuff.



I would be interested in a long term review of the battle born battery lifepo4. I may switch to a single commercial lifepo4 that supports at least 200a rms with an isolator and bms in the future. My main concern with lifepo4 is thermal runaway. The cell quality, factory balancing, and BMS seem to be getting better on these so less of a concern for me as time goes on. Seem to be more options these days that have the isolator and bms all in one package with the cells.

 

[212s]

Im not exactly sure of the build date but I’m guessing it was late 2019 or early 2020 as I saw the boat online at the dealership as early as late February of 2020.

Your Hull number has the date code in it - YAMxxxxxMYmy - where M is a letter presenting the month the build started so mine is a B, Y is a number for the year of build so mine is a 0, and my are numbers for the model year so mine is 20.

Thanks a lot for going out and checking voltages for me!

No worries...I'm curious to know why mine is pretty much bang on while yours is off by that much.

 

[Nick Hughes]

Old thread but just getting around to doing this. I cut the AUX batt and SYS batt lines from the left wire cluster and then wired 2 wires to the positive terminals. Now I have the errors on my screen. What did I do wrong? The 2 wires I clipped go no where now, I wired these new into the harness. TIA.

 

[Nick Hughes]

Old thread but just getting around to doing this. I cut the AUX batt and SYS batt lines from the left wire cluster and then wired 2 wires to the positive terminals. Now I have the errors on my screen. What did I do wrong? The 2 wires I clipped go no where now, I wired these new into the harness. TIA.

So I hooked up everything it was and same error. The reason I’m even doing this is because my house battery needs replaced and I was annoyed for both readings to be the house. Anyways, I think my 5v house might be actually causing the issue. Being replaced tomorrow.

 

[212s]

So I hooked up everything it was and same error. The reason I’m even doing this is because my house battery needs replaced and I was annoyed for both readings to be the house. Anyways, I think my 5v house might be actually causing the issue. Being replaced tomorrow.

You're getting a 5v reading on the house???
If so, that battery is probably toast and may be the cause of your issues...

 

[212s]

I'm curious to know why mine is pretty much bang on while yours is off by that much.

@FSH 210 Sport
Did you get this resolved? I'm curious about the differences and why...

 

[FSH 210 Sport]

@FSH 210 Sport
Did you get this resolved? I'm curious about the differences and why...

Sorry, I was remiss in not responding sooner.

No, the reading is .4 volts low on the connext screen compared to my fluke meter. I just raise the connext voltage in my head when I look at it. When the start and house batteries are fully charged I see 14.1 V on the connext while underway which is just about perfect voltage at 14.5 adjusted voltage with the electrical load of the engines, instrument, and my fish finder running, I haven’t tried putting anymore accessory load on the bus to see if the voltage starts dropping. As far as I can tell from the measurements I’ve made the voltage difference is linear, always .4 volts low. My friend is pretty sure that there is a zener diode some where in the mix that will drop the voltage read.

While it’s a bit annoying I’m willing to let this mystery ride since it doesn’t appear to be affecting anything negatively ?

 

[Nick Hughes]

You're getting a 5v reading on the house???
If so, that battery is probably toast and may be the cause of your issues...

Yeah, it all the sudden stopped holding a charge. 10 mins of floating stereo and it starts beeping.

 

[Nick Hughes]

Yeah, it all the sudden stopped holding a charge. 10 mins of floating stereo and it starts beeping.

Sorry for the spam, that was it. Replaced my 24EV House Battery from 2015 with a group 27 and now everything is working as planned. Next up, why doesnt my shower pump work....BOAT.