Battery Compartment Wiring

[RVhiker]

For my new Jayco 28.5RLS fifth wheel, I have a question about the wiring in my battery compartment.

At the battery positive:
1) There is one orange 12 gauge wire connected.
2) There is one green 12 gauge wire connected, that goes into a 30 amp fuse holder. The wire coming out of that fuse holder is connected to two 10 gauge round black cables.

Where does the orange wire go? Why isn't it fused?
Where do the 2 10 gauge black wires go?

[jamoke]

12 gauge orange wire supplies power for break-away brakes. I measured 12 amps on this wire when the breakaway cable is removed.

My rig has a green 10 gauge wire with a 30a inline fuse..connected to SINGLE 8 gauge black wire that goes to the Progressive Dynamics charger/converter/distribution. Not sure where your second black wire would go unless they are doubling up due to length.

I plan on removing the 10 gauge wire and fuse and installing a 50 amp Blue Sea breaker with switch to both wires.
Blue Sea Breaker

[Seann45]

Second wire comes from the hitch? to recharge the batteries?

[Bob Landry]

You'll need to open the junction box on the front of the frame and see what is connected where. The white wire from the battery is ground and is probably connected to the chassis close to the battery. The wire with the fuse is going to go to the converter. I would trace down the other black wire and see for sure where it goes. I doubt Jayco used a double wire to handle feed to the converter as it would have been easier to just run one heavier wire. The 30A fuse also makes me think that's not the case or else they would have protected the double wire run with a heavier fuse. If it's not connected as a ground, check the manual for your coverter and make sure there isn't two 12V inpust for the converter before you do anything with either black wire. I'm guessing that one black wire goes to the DC distribution for when you aren't plugged into shore power, and the other is the wire that the converter uses to charge the battery when you are plugged in, since the battery is diabled on shore power but still need to be maintained(charged)Also, I wouldn't up the size of the 30A fuse. it was sized that way for a reason. I also would not increase the size of the 30A fuse without calling Jayco. it was sized that way for a reason., probably because they used 10ga wire and it's only good for 30A. Just my guess.

[RVhiker]

You guys gave me some good leads. There's a big wad of wiring connected near the pin box - I think answers to some of the mysteries lie there.

My unproven supposition is that the orange wire connects to the break away and also carries charging current from the tow vehicle. I find the two 10 gauge cables connected together on the other side of the 30 amp fuse confusing. We'll see when I tear into it. I will be installing a battery disconnect switch near the converter, and I want to understand what is connected to what before I begin. My voltmeter should tell me the answers.

[yesmar]

battery got stolen from jayco 185rb, wiring got cut. I need help identifying the termination point for cut wiring. please help !!!!!

[RedHorse1]

Is one of the black wires feeding the power tongue jack?