Need help, hoping for help on wiring issue

[mleads310]

I was cleaning my battery terminals on my sailfish yesterday and noticed one of my negative wires was sparking, giving positive feedback which is a no no. Traced that line to the negative bus bar under the helm/steering. There's aprox 11 black wires going to this bar. I removed each one and found that 2 of them have positive feed!!!!!! One of them is a constant positive and the other only comes on when I hit the navigation light switch??????

Now I'm totally confused!!!!.
I tried tracing these wires back as far as I could. The majority of them (7 if I remember correctly) lead to a white plug (1 of 3 white plugs in the same area) in the upper area starboard of the 704 binnacle. FYI I can not drop these plugs as they are tied up in there in a way that its impossible without destroying. So I unclipped the white plug to test and confirm if I was getting positive from any of the pins, and I was!! I got constant positive and I don't know where this plug is coming from to trace it back???

Side note, I also followed the positive wire back to the positive bar under the helm/steering and it only has 2 red wires. 1-feeding the switch panel (I believe), the other going into another white plug (same area of the 3 white plugs) with various other colors.

i will take some pictures today as I've been driving myself crazy trying to understand this and understand how my boats been running like this for 3 years and not signs of issues.

 

[seasick]

If the ground is open as it would be when you undid the connection and one or more loads is connected to the positive buss, voltage will appear at the unconnected ground terminal.
In other words, what you see is to be expected. If you saw sparking at the negative wire at the battery, that connection has a problem.

 

[mleads310]

Seasick that is a great help, I never knew that you can read voltage at the negative end if the negative end is open and the positive is closed/connected to pos buss.

What I seen was not a severe spark by any means but more like a slight crackle spark if that makes sense. Could this be due to the fact that I disconnected the negative terminal (open) while the positive terminal was still connected to the buss (closed)?

 

[mleads310]

I'm still going to get a few pictures of that white connection/plug/harness for your input as to why I'm getting constant pos from one of the black wires coming from it. If that's ok?

 

[DennisG01]

If the circuit is on/drawing power (a bilge pump float switch, for example, would always be on), it's not uncommon to get a little spark.

 

[mleads310]

This picture is looking in from the bathroom/head panel facing aft. The connections you can see are coming into the helm, the other side of the connections that you can't see are routed up then down helm somewhere towards aft of boat. So basically you are looking at what is coming from the buss bars into this connection side. The buss bars themselves are being fed by separate pos/neg which I have traced with no issue.
The yellow arrow is pointing towards the black wire that is getting constant 12v when I put my battery switches on. This black wire along with the other black wires in this photo are all connected to the neg buss. The blue arrow is pointing to the red wire, this is coming from the post buss (not sure if this info is needed but I figured I would reference it since is sorta tied together.

 

[DennisG01]

Another way to look at this... is everything working properly? If so, don't go looking for problems!

 

[mleads310]

Lol. I know I know but when I heard that crackle with little tiny spark my mind started going bananas. I guess my biggest concern is that one black wire coming from that plug that has a constant 12 volts. That black wire is going to the negative bus, along with the other black wires, and that negative bus is a direct line to the negative battery

 

[glacierbaze]

What do they read when connected to the neg buss?
What is the read on that black wire with the battery switch off? If still positive, that narrows down your search considerably, to something like bilge pump connections, and the memory for your radio. If it goes away, I would want to know what circuit is switched on that I was not aware of.

 

[seasick]

What do they read when connected to the neg buss?
What is the read on that black wire with the battery switch off? If still positive, that narrows down your search considerably, to something like bilge pump connections, and the memory for your radio. If it goes away, I would want to know what circuit is switched on that I was not aware of.

If you got a little spark when you reconnected the ground wire at the battery, that is to be expected if (as several members have said) something is drawing power. As mentioned, that could be a bilge pump if it is calling for pumping or is an electronic type that always draw a bit of current. As also mentioned, it could be the stereo memory feed that is always powered up. It could be any load that is drawing power. Regardless, there is nothing to worry about at this time
.If you have parallel connected batteries, a spark is also possible since two batteries probably wouldn't have the same exact resting voltage and when you connect the ground, one battery kind of discharges the other for a brief of time until booth batteries are at the same voltage

 

[mleads310]

With the battery switch off nothing is showing volts. With the battery switch on the meter is showing that the black wire is positive and at 9.8volts. here's the crazy thing. When I put that black wire to the ground bus, it powers up my overhead electronics???? Could one of those electronics, vhf, radio, spreader/some lights, auxillary light, spot light.....be back feeding?

So I go up to my electronics box to the fuse panel that I have set up there. This is what I found out so far I'm still halfway through testing everything.
My dome light / spreader wires either is connected incorrectly or is defective because it is backfeeding positive on the ground side at 9/volts. If anyone has a pictured diagram or wiring schematic for that I would greatly appreciate it. I have four wires coming out of it red,red,blue and gray.
Next I'm getting about 3 volts on my negative side of my fusion radio.
And I'm also getting just over 4 volts from my VHF.

Both the VHF and the radio are installed and wired correctly I did them myself a few years ago. Plus it's pretty simple positive and negative wires so I just double-checked and everything is correct.

 

[mleads310]

Again guys I really appreciate all your help. I'm sure you understand how nerve-wracking it is trying to get the boat ready for the season and then stumbling across this. for now I'm going to be hooking everything back up except for the dome spreader lights as I feel nine volts coming back on the negative terminal is way too much????

 

[mleads310]

And correction on the dome light wires I have. Black gray blue red

 

[SkunkBoat]

I think you are overthinking this and creating a "problem" by measuring something that is not there until you measure it.

A black "ground" wire is only at ground potential when it is connected to ground. You are disconnecting it from ground and measuring it. Thats not telling you anything.

You say that "When I put that black wire to the ground bus, it powers up my overhead electronics". What you are doing is reconnecting the ground to the overhead electronics.

I suggest that you put everything back as it was and see if something doesn't work. Then we can help you with that problem.

Sometimes text does not convey tone, please don't read this as anything but a calm but concise description of your problem.

 

[mleads310]

Hey skunkboat trust me I take this all as good advice. I know it's hard through typing and messaging but I'm taking this all in as a positive. And I'm more than appreciative for any and all input.

okay I put everything back together with the exception of the dome/spreader wires. The reason I didn't put that back is because they are all four wires. The blue one automatically has a connection to another blue wire that runs somewhere out of the electronic box, so the blue wires out of the equation. Then I'm left with the black, gray and red wire. Someone previously spliced the black wire and made that red as well which makes me think it may be hooked up incorrectly. If by any chance anybody has pictures of the way it should be wired up I would be appreciative.
Everything else seems to be working fine. In addition I found a bad battery combiner that I didn't even know existed for my bow thruster. Only realized something was wrong with it after the thruster battery wasn't charging. I measured the resistance of the battery combiner, as well as excluded it from the equation and determined it was faulty so I just ordered another one.

Again I thank everybody for the rent put trust me I take all in Goodwill. Let me know if anyone is able to find the wiring for that dome light.

 

[SkunkBoat]

Need your exact model numer & year for accurate diagram.
Go to owners-manuals and get the one you need.

Generally, gray is nav lights(bow), gray/red is Mast light, Dark blue is cockpit/cabin lights, dark blue/white is spreader lights.

Some models/years have a fuse panel in the hardtop which could be fed by 10 gauge Red and 10 gauge Black

...or there could be a 10 gauge Blue/Black and 10 gauge Blue/Red feeding the hardtop...
...or even a 10 gauge Red/White and 10 gauge Black/White in the hardtop for "VHF"

 

[mleads310]

I have a 2001 282. The wires I'm referring to are in regards to the dome courtesy/ spreader light combo..... That combo light that is attached to underneath the electronics box. It's a dual switch one controls the spreader lights and one controls the actual dome light. There's nothing in the manual referencing the wires for the actual light. They referenced the light bulb and the part number but that's about it.

 

[Blaugrana]

How many positive and ground wires do you have going to the fuse panel from the dome light? I believe I had 2 power and 1 ground. I know I had a light blue wire being connected to a dark blue one that then left my hardtop. The wires were all taped up leading me to believe that somehow 1 wire became 2 somewhere in that bundling of tape

Do a search on dome light as someone had questions on how to wire their dome light last month? It might help you figure out how the wiring should be.

 

[mleads310]

This is the way it was before I disconnected it was:

Blue wire-connected to another blue wire that exists electronic box
Grey- went to fuse block 10amp
Red-went fuse block 15amp
Red again, which I find out to really be black at the source- went to ground block

Not sure if this matters but in the middle of going nuts today, I also realized one if the switches for the courtesy/dome light didn't operate correctly....I could only get operation for the red bulb but not the white. So I ordered a new switch from digikey. I'm just a little dumbfounded how the negative from this courtesy/dome could kick back 9 volts.

 

[Blaugrana]

Is it kicking back 9 volts or just not working as expected? Have you tried measuring with each button pressed?

Maybe you have it powered on and it is in the white light setting but doesn’t work. It’s pulling volts and you think it’s off but isn’t and that is why you are measuring volts on the bus.. Press the button and measure after each time.