2020 242 SE Battery Connection Question

[Drexx3]

Was looking at the battery connections today as I had a strange issue where if I were to turn off the start battery the Connext would throw a BCU Error. In studying the service manual and the battery lead connections I seem to have an additional positive lead not referenced.in the picture below my start battery is on the last and house is on the right. The house battery has the positive house lead coming from the house battery switch, as well as various ground connections. The start battery should have the positive start lead coming from the start battery switch, two negative leads (one from each engine), the DVSR connection, and finally the negative jumper lead to the negative terminal of the house battery. There’s a second positive lead connected to the start battery with the label “BATT” which after about a foot connects to an in-line fuse labeled “BOAT FUSE” (visible at the bottom of the picture below) then continues not to either of the switches but instead up over the switches towards the engine compartment. The second photo below attempts to show a perspective showing the wire bypassing the switch. Does anyone know what this connects to And should it be on the house battery instead?

 

[sunbyrned]

I don't know if this information helps you at all. I would suggest following the wire that leads into the engine compartment and see what it's attached to. For example, I installed a high water alarm in the engine compartment which involves a fuse as you're mentioning, and I had to run the wire through the barrier wall to the batteries. Perhaps your boat has an alarm or a second bilge, etc.. Here are the instructions I followed to install my alarm. Maybe this and the diagram attached can somehow help you trouble shoot to figure out if it needs a positive or negative connection.

BoatUS Expert Advice

BoatUS Magazine, the largest boating magazine in the US, provides boating skills, DIY maintenance, safety and news from top experts.

www.boatus.com

 

[marcham]

I suspect that the 2nd red wire on the start battery could be for the automatic mode of the bilge pump? What size fuse does it use?

 

[redthumper9]

Pretty sure it's the wire to your amp. Goes to house battery.

 

[marcham]

Good point. Pull the fuse and identify what does not work.

 

[TommyG]

First, my understanding is these “E” series boats require both house and start batt switches to be on. That being said...

Seems to be a trend. Not sure if it’s a factory wiring issue, dealer (who Installs the batts) or what, but I had a similar situation w my new 2019 242X. My start battery was draining while in float mode w the ignition off, radio on and emergency parallel off (untied). Both battErie’s charge (~14 v ) while running the boat. There should be no load on the start Batt while in float because of the VSR. After looking at the batteries, I found a few issues in comparison to the wiring diagram.

1. One of the wire bundles coming from the Amp fuses (that go to the tower) was connected to the start batt like yours.
2. There was a neg “amp” cable also connected to the neg of the start batt (not a big deal because there’s a common gnd.)
3. There were too many negative wire groups to stick to the 3 wire connections per battery post rule of thumb.

I tried to connect the positive (red) “amp” wire to the house batt but the cable is not long enough. So since its a new boat and under warranty, I took it to the shop today.

It makes sense to me that the only things connected to the start batt should be the engines, the VSR and the neg jumper (if required ). I suspect they will need to combine two of the wire bundles and connect the second positive “amp“bundle to the house batt. But that is my novice speculation based on my understanding of the system.

I will try to upload pics later and report back when I get my boat back.

Thoughts?

 

[redthumper9]

Sounds about right..... When I took delivery of my boat, there were several issues with the way the dealer installed the batteries (stuff hooked to the start battery and vice versa). I immediately added an extra house battery and onboard charger so I sorted it all myself.

 

[Mattgar33]

I also am having some sort of electrical problems. it started with bad batteries that failed after a year from Panama City cycle/dealer.
So I sprung for 2 Optima marine batteries hoping that would solve my issues.
I was careful to video/photograph original wiring locations (from when I got from dealer)
everything worked fine for a month...parked boat for maybe 2 weeks and dropped in water.
I noticed after turning on start/house batteries the LED touch screen didn’t light up...but engines started
It was a super hot day and I only 10th time out on it; figured maybe just a glitch and I was running a short distance to small island.
Ultimately fiddling with it while kids had fun w mom; house battery was LOW voltage like 8.5. Only way LED screen would come on was in emergency parallel mode
I thought maybe new battery either damaged or had been run down by a an accessory wrongly wired/shorting

I flipped emergency parallel on to start when we left and flipped it off while running.
House battery was low enough boat turned off screen and all navigation lights/all boat controls other than engine/steering obviously
Flipped Emerg Parallel back on, LED screen comes back but boat freaks out and says stop both engines and call Yamaha for service.
I ran it the 10 min back to trailer and have since checked connections, charged both batteries fully.
House battery and start switches on line normal, LED screen lights up fine now (without emerg parallel) But boat warning freaks out as soon as I turn key power on and gives same error.
Seems like maybe the voltage/amp mess maybe damaged a sensor or blew a fuse on something triggering a warning?
Engines run fine - photo of error attached r

 

[TommyG]

I also am having some sort of electrical problems. it started with bad batteries that failed after a year from Panama City cycle/dealer.
So I sprung for 2 Optima marine batteries hoping that would solve my issues.
I was careful to video/photograph original wiring locations (from when I got from dealer)
everything worked fine for a month...parked boat for maybe 2 weeks and dropped in water.
I noticed after turning on start/house batteries the LED touch screen didn’t light up...but engines started
It was a super hot day and I only 10th time out on it; figured maybe just a glitch and I was running a short distance to small island.
Ultimately fiddling with it while kids had fun w mom; house battery was LOW voltage like 8.5. Only way LED screen would come on was in emergency parallel mode
I thought maybe new battery either damaged or had been run down by a an accessory wrongly wired/shorting

I flipped emergency parallel on to start when we left and flipped it off while running.
House battery was low enough boat turned off screen and all navigation lights/all boat controls other than engine/steering obviously
Flipped Emerg Parallel back on, LED screen comes back but boat freaks out and says stop both engines and call Yamaha for service.
I ran it the 10 min back to trailer and have since checked connections, charged both batteries fully.
House battery and start switches on line normal, LED screen lights up fine now (without emerg parallel) But boat warning freaks out as soon as I turn key power on and gives same error.
Seems like maybe the voltage/amp mess maybe damaged a sensor or blew a fuse on something triggering a warning?
Engines run fine - photo of error attachedView attachment 124835 r

Mine was exhibiting similar behavior. There are like 3 computers and your screen on these boats. When I took mine in they said I had a bad touchscreen. Replaced it and now it has been working fine for the last 6-7 outings. I drive around for about 30-40 mins then Float Mode for about 4-5 hours w music and batteries do not loose charge. Not sure if they actually did anything w the wiring.

 

[TGinNY]

float mode.... can’t find anything in the manual about this. Can you guys give more info on that? I have 2020 242SE

thank you

 

[Mattgar33]

Mine was exhibiting similar behavior. There are like 3 computers and your screen on these boats. When I took mine in they said I had a bad touchscreen. Replaced it and now it has been working fine for the last 6-7 outings. I drive around for about 30-40 mins then Float Mode for about 4-5 hours w music and batteries do not loose charge. Not sure if they actually did anything w the wiring.

thanks, yeah I feel like no choice but to take it in...all this computer garbage is lame. Won’t buy another yamaha...my seadoo was better

 

[TommyG]

float mode.... can’t find anything in the manual about this. Can you guys give more info on that? I have 2020 242SE

thank you

It's basically in water standby mode. I'm not sure if this is an addition starting with the 2019's but On the E-series boats (with the push button starts) you leave the main Key in the ignition position when you want to relax and Anchor. If you turn it to "Off" you can not use the console or any accessories like the radio because it will power off the Connex screen. With the Master Key in the ignition position the boat automatically senses that you are in the water with the engines off and Show's "float mode" at the top. Essential it just changes the display to give you water temp, depth, the current charge on both batteries and access radio, lights etc. It's more convenient since you don't need RPM or throttle position info on the digital display.

Around Page 88 under Instrument Operation in the 2019 Manual (search "Float") in the online manual search bar.

 

[Quad]

It's basically in water standby mode. I'm not sure if this is an addition starting with the 2019's but On the E-series boats (with the push button starts) you leave the main Key in the ignition position when you want to relax and Anchor. If you turn it to "Off" you can not use the console or any accessories like the radio because it will power off the Connex screen. With the Master Key in the ignition position the boat automatically senses that you are in the water with the engines off and Show's "float mode" at the top. Essential it just changes the display to give you water temp, depth, the current charge on both batteries and access radio, lights etc. It's more convenient since you don't need RPM or throttle position info on the digital display.

Around Page 88 under Instrument Operation in the 2019 Manual (search "Float") in the online manual search bar.

On my 2020, if the key is off you can power on the Connext system by pressing either Bilge or pressing and holding the auxiliary button. Pressing and holding auxiliary again for 10 seconds will turn it off.