Which wire to positive on battery

[allkidd]

It has been over a year since we got the camper out and I don't remember which wires go to positive and negative. I've got one battery and one red wire and two white wires. I know color doesn't mean much but I thought that I would mention it. The red wire is thicker than the other two.

I vaguely thought I remembered the red to positive and the other two to negative. But, when I hook it up like this the lights are dim and do not charge when I plugged into 110. Everything works except the lights and furnace. My converter is only a couple years old. Since I wasn't very sure about the wire connections, I'm thinking it had to be that I don't have them on correctly.

I've tried followiing the wires but it is very difficult as they seem to disappear under the floor. Like a car, would the negative actually go the frame?

Is there a way to figure this out using a multimeter?

Thanks in advance for any help!

[NinerBikes]

I'm thinking we were all trolled by the OP.

[MEXICOWANDERER]

Oh ****, I typed an earlier post in invisible ink...

[2oldman]

This tutorial may be of some help. 12v side of life.

To fully understand a MM, you need to know what DC is and what AC is.

[westend]

Strabo wrote:

fitznj wrote:
Get a multimeter from WalMart (real cheap) and use to to test each wire - this will a sure way of knowing which wire is Pos and Neg.

Xlnt suggestion......Now teach us people like me how to use it,I mean it. I have no idea where to start setting the dial, maybe you could start a thread, slowly teaching us old guys who want to learn about how to use a multi meter.

Raise your hand if you would like to learn about too?

A Google search turned up 4 million hits but here's the basics about Multimeter usage

[NinerBikes]

Red wire to positive.

[RJsfishin]

Forget the converter, as the issue is identifying pos & neg batt cables.
Heres a new idea,.......that I think will work

Set battery on the ground, connect jumper cables to battery,....connect negative jumper to trailer frame/ground.
Touch positive jumper to each battery cable in question, BUT ONLY W/ A 20-30 AMP CIRCUIT BREAKER IN SERIES WITH THE POS JUMPER !!
Any battery cable that trips the CB, is a negative cable
Any cable that doesn't trip the CB, is a positive cable

The cost of this method is the price of a CB at the auto parts

[Strabo]

fitznj wrote:
Get a multimeter from WalMart (real cheap) and use to to test each wire - this will a sure way of knowing which wire is Pos and Neg.

Xlnt suggestion......Now teach us people like me how to use it,I mean it. I have no idea where to start setting the dial, maybe you could start a thread, slowly teaching us old guys who want to learn about how to use a multi meter.

Raise your hand if you would like to learn about too?

[westend]

Trip to dealer, guess which goes where, or buy a meter and know forever where there is voltage and where there is frame ground.

[time2roll]

With dim lights when plugged in... I am also testing if the converter even works.
By now it could also be the main fuses.

Got to start somewhere or haul it down to the dealer.

[2oldman]

Sm..Oh I see..you're testing the converter polarity.

[mrekim]

2oldman wrote:

fitznj wrote:
Get a multimeter from WalMart (real cheap) and use to to test each wire - this will a sure way of knowing which wire is Pos and Neg.

How?

The ground(-) wire will be a short to the chassis. The positive will not.


Assuming the meter is set up to beep when there's a short.

1) Unplug all electricity. No 110, no battery.

2) connect one end of the meter to a clean metal on the frame - a clean bolt or sheet metal screw that goes into the frame.

3) Connect the the other end to each wire, one at a time.

The ground wire(s) should beep. The (+) wire should not.


As a double check, you can find the +12v pin on the tow plug and verify that the the (+) wire is connected to that by putting one lead on the (+) wire and one on the +12v pin.

smkettner wrote:
Set meter to 20 volt DC scale. Plug in the RV and measure voltage between red and white(1) and white(2).

Post the results.

This should work too. Just be sure that the lugs on those three wires don't touch anything during your test....

[time2roll]

2oldman wrote:

fitznj wrote:
Get a multimeter from WalMart (real cheap) and use to to test each wire - this will a sure way of knowing which wire is Pos and Neg.

How?

Set meter to 20 volt DC scale. Plug in the RV and measure voltage between red and white(1) and white(2).

Post the results.

[MEXICOWANDERER]

Thicker - thickest? Now, pray tell, how did a camper manufacturer swindle Professor Kirchoff out of his Just Desserts?

[RJsfishin]

Fulltimer50 wrote:
Red is usually positive and black is usually negative in a DC system. White is not a DC color. You will have to do as has been suggested and trace the whites back to see where they go. Since there are white wires I would also trace the red back as there is no guarantee that the red is positive either.

Where does this wrong info come from ?
Red is usually positive
Black could be negative, but only when used in the same circuit as the red. Otherwise black is almost never negative. And black is always positive when used in the same circuit as white.
And white certainly is a DC color. Almost every dc light fixture, and every cigar liter socket uses black and white wires, in which black is always positive, and white is always neg ground. WHEW !!

[dougrainer]

The point on this mans problem is simple. He only has 3 wires to choose from. 1 wire is RED and the other 2 are WHITE. So, it is obvious that the RED is Positive and the WHITES are Ground. Take it from someone who has worked on these system for 37 years. Doug
PS, I have NEVER seen a Battery cable, AT THE BATTERY, that is White that is NOT a Neg(ground) wire.