One positive wire straight to house battery

[FLJetBoater]

So I was tinkering with my batteries tonight adding in a Bluetooth device and when I took the 4 switches off the wall and looked at the house wiring, there’s 2 wires coming off the house battery. 1 wire goes straight to the switch, 2nd wire goes towards the switch but peels off and goes into the bundle of wires coming off the switch. To me this means something in the boat is hard wired straight to the house battery and not switched. Anyone have any idea what it would be?

asking before I spend too much time tracing this wire....

 

[Sean R]

Bilge pump, maybe.

 

[FLJetBoater]

Bilge pump, maybe.

If it was, I assume the light would come on when I flip the switch?

 

[Babin Farms]

If it was, I assume the light would come on when I flip the switch?

It should.

Maybe it's the constant power lead for the radio to keep all of the settings when the battery switch is off?? Or do you lose all of those when switched off?

 

[sunbyrned]

I installed a high water alarm and wired it directly to the battery. This is so it would come on even if the battery switches were off. Maybe you have a second bilge or high water alarm, or something that makes sense for it to come on when needed.(?) On a side note, when installing a stern remote, I found a ton of extra wires underneath the starboard rear storage compartment. There was actually a wire hanging in there specifically for the remote. It could be used for anything though. I got access to it through the black cover separating the engine compartment and the storage compartment. Just letting you know. Maybe there's something there you can use for your bluetooth device.

 

[Ronnie]

Could it be for the head unit (to keep the head unit settings even when the battery switches are in the off position)?

 

[Frank Marshall]

The bilge pump on my FSH 210 is wired direct to the battery. The switch on the helm is wired through the house battery switch. When I turn the Bilge Pump switch to on, the bilge starts pumping water or not. The switch is really a means to confirm the pump works. With a charged battery the bilge is always on with the direct wire.

 

[FLJetBoater]

It should.

Maybe it's the constant power lead for the radio to keep all of the settings when the battery switch is off?? Or do you lose all of those when switched off?

bilge light does not come on when house battery is off. So assuming it's not that. It could be the constant power for the stereo - that would make sense. The wire is red/white striped, I'll see if there's one like that coming out in the helm later.

 

[FLJetBoater]

The bilge pump on my FSH 210 is wired direct to the battery. The switch on the helm is wired through the house battery switch. When I turn the Bilge Pump switch to on, the bilge starts pumping water or not. The switch is really a means to confirm the pump works. With a charged battery the bilge is always on with the direct wire.

I think that's only in the newer boats. In 2014 the switch has to be on for the bilge to operate at all. Then, once the switch is on it runs every 5 mins or so to check for water.

 

[FLJetBoater]

I installed a high water alarm and wired it directly to the battery. This is so it would come on even if the battery switches were off. Maybe you have a second bilge or high water alarm, or something that makes sense for it to come on when needed.(?) On a side note, when installing a stern remote, I found a ton of extra wires underneath the starboard rear storage compartment. There was actually a wire hanging in there specifically for the remote. It could be used for anything though. I got access to it through the black cover separating the engine compartment and the storage compartment. Just letting you know. Maybe there's something there you can use for your bluetooth device.

View attachment 133117

Thanks. I already did the work in the battery compartment to wire up the bluetooth connection. Ran wetsounds RCAx6 from helm to battery compartment. Hooked 2 up to the bluetooth, and the other 4 will be for the outs from the head unit to the amps.

 

[Julian]

Take a close look at the wire....many wires in the boat have writing on them for what they are....perhaps it says on it???

 

[Frank Marshall]

Sorry, didn't notice the older boat. I agree, I think the wiring change like my 2018 came about in 2018.

 

[Quad]

I was looking at this today - 2020 242SE. One wire says "house" and goes to the house switch, the other says "batt" and I can't track it once it gets into the engine compartment.

At this point, the only thing i can think of that would need a wire that big would be the Wetsounds amp. The older service manual I've found shows that previous years of the 242XE had amps directly to the battery, i might see if that's the case with mine.

 

[Quad]

Update!

I took a few minutes to probe around with wires to figure out what was what.

1. The "BATT" cable connected to the House battery appears to go directly to the Wetsounds amp in front of the helm. I can't tell if this branches anywhere between the battery and the amp, but it appears the amp is its primary purpose. That said, I can absolutely confirm that it does not supply power to the Bilge pump mains.
2. The bilge pump absolutely has its mains supplied with power before the main House and Start switches.
3. Things get weird with the bilge, and I'm still trying to figure this out. Basically, I can't tell which battery supplies power to the bilge. I disconnected all positive leads from both batteries and attached the "START" and "HOUSE" cables independently. In each scenario, the bilge mains had 12+v, which leads me to believe that the bilge is attached somewhere in the Emergency Parallel switch. In the event of a short in the windings, this could get interesting and cause a power leak, assuming it doesn't just burn and cause an open circuit.
4. Depending on the wire gauge and the current draw of the amp, it's possible that those supply wires could be repurposed and used to supply a fuse panel for other purposes under the helm. Note that this is NOT a switched supply.

At any rate, I feel like I can confidently turn off the "HOUSE" switch in the future when the boat is on its mooring. Additionally, I'm seriously considering the possibility that I may not need to use the 1/0 gauge wire that I purchased for my under-helm fuse panel, or at the very least, that I may be able to drive the amp at the fuse panel instead of having it directly tied to the battery.

 

[Quad]

Just to complete the conversation: The wire gauge for the cables from House battery to the Wetsounds amp on the 2020 242SE is 6 AWG.