Forum Discussion

Explorer

May 02, 2015

What are these wires for?

I have a question about how and why my batteries are connected the way they are.

I had the battery covers off, and was gonna pull the batteries out to test fit a toolbox on the a-frame but alas, it won't fit between the propane tanks and the front of the trailer.

Anyway, there's the negative from the first 6 volt, then a jumper to the second 6 volt, then the positive, making 12 volts. Makes sense so far, right?

There was also a pair of 10 gauge wires with #10 studs jammed under the 3/8" lugs of the jumper cable. And it was red to the positive off the first battery and white to the negative of the second battery. I don't know what it's for, but as I see it, there's zero potential there. I'll post a pic of it for clarification shortly.

Any ideas?

34 Replies

Ranger_Smith
Explorer
May 02, 2015
It seems that the trailer is operating on 6 volts. If you look in the middle of the batteries I believe that is the harness that feeds the trailer. The red wire should go to the plus with nothing on it and the white connects to the negative with the white on the other battery.
SCVJeff
Explorer
May 02, 2015
What I see is a 6 volt source from one battery only. Is this a new trailer, or has it recently been worked on?
bigrigfixer
Explorer
May 02, 2015
Temperature compensator?

Turns out the pic I posted is in a double post... I'll put it here too.
westend
Explorer
May 02, 2015
What you describe is the correct series wiring for 2 x 6 V batteries. The Negative from one 6 V is connected to the Positive of the other 6 V. The power output leads should be attached to the end posts of the two batteries, not on the two (-), (+) jumpers. That would be true for any lighter wires,as well.

6 V's wired in series with temperature compensation sensor wire on jumper (as such, it draws no power):

BTW, any fuses or circuit breakers in sight?