We are putting in a new battery and have a white cable and a red cable coming out of the trailer frame.Does the White go on the Negative battery terminal?The Red go on to the Positive battery terminal?Thanks!

Yes, white is negative in this case.

Ok thanks, we haven't done it in awhile so want to confirm what we are doing first.Just watched a You Tube video and it says connect the White (-) Cable first.Then connect the Red Cable.Thank you.

White cable first? Every book and manual I have read says connect the battery ground (white) last so your wrench or plier will not complete the circuit.

Actually you would connect the battery positive first the the negative. If the positive cable goes on first and the wrench was to accidental touch the frame it wouldn't short out and spark. Then when you put the negative on and when you swing the wrench it cant short to the frame as it is the frame. The danger comes in and most accidents happen when the wrench touches between the two battery terminals. It will absolutely go into melt down and can blow molten lead battery terminal or wrench metal into your face. Wear some sort of eye protection at minimum and proper battery service often requires a full face shield to be done safely. Use a short wrench or wrap it in electrical tape for servicing your batteries if they make you nervous.

Let this post be a reminder to others take a PICTURE of the cables BEFORE you disconnect them.

Battery hook up red and white cable HELP | Good Sam Community

21 Replies

2oldman
Explorer II
Aug 27, 2014
Old-Biscuit wrote:
I'd be more concerned in blowing 'reverse polarity' fuses on converter when cables are backwards.
Well, that'd be another way of knowing, assuming turning the converter off wouldn't stop it from happening.
Old-Biscuit
Explorer III
Aug 27, 2014
dave17352 wrote:
2oldman wrote:
lots2seeinmyrv wrote:
We labeled the cables when we removed the dead battery. The TT went in the shop and someone took our labels off!
Ouch.

What I do is simple. Turn everything off. Connect batteries. Turn on a fan. If the fan runs correctly, you're good. If backwards, reverse wires. Done.

I think your fan would run either way.

2oldman covered that.

I'd be more concerned in blowing 'reverse polarity' fuses on converter when cables are backwards.

Follow cable to to frame/ground.
MEXICOWANDERER
Explorer
Aug 27, 2014
Took the labels off, eh?

THIS IS A USEFUL ACCESSORY WHEN TALKING TO SERVICE MANAGERS WHO CANNOT WALK AND CHEW GUM
dave17352
Explorer
Aug 27, 2014
2oldman wrote:
lots2seeinmyrv wrote:
We labeled the cables when we removed the dead battery. The TT went in the shop and someone took our labels off!
Ouch.

What I do is simple. Turn everything off. Connect batteries. Turn on a fan. If the fan runs correctly, you're good. If backwards, reverse wires. Done.

I think your fan would run either way.
time2roll
Nomad
Aug 27, 2014
RJsfishin wrote:
False accusations will get you nowhere !
The RV guy never did say which cable to hook up first. It did show him touching the white wire first, but then it fell back off while connecting the positive. In reality, it showed him connecting both at the same time.

Well,....somebody had to defend the poor RV guy !! :)

And make them more than finger tight also :R
johntank
Explorer
Aug 27, 2014
RJsfishin wrote:
False accusations will get you nowhere !
The RV guy never did say which cable to hook up first. It did show him touching the white wire first, but then it fell back off while connecting the positive. In reality, it showed him connecting both at the same time.

Well,....somebody had to defend the poor RV guy !! :)

I agree that is the way I saw it too.
joshuajim
Explorer II
Aug 27, 2014
To be on the safe side, take your VOM set on ohms and touch each wire while touching the frame. One will have continuity one will have some ohms due to anything that is turned on.

Continuity is ground regardless of color.
RJsfishin
Explorer
Aug 27, 2014
False accusations will get you nowhere !
The RV guy never did say which cable to hook up first. It did show him touching the white wire first, but then it fell back off while connecting the positive. In reality, it showed him connecting both at the same time.

Well,....somebody had to defend the poor RV guy !! :)
BTPO1
Explorer
Aug 26, 2014
Old-Biscuit wrote:
Always connect positive cable 1st.....then ground cable.
Reverse when disconnecting.

AND..follow that white cable and check that it is attached to trailer frame (ground)....nothing standard with trailer mfg. cable colors :S

I agree with Old Biscuit on this one. You should always follow the cable and see where it goes. You can't go wrong if you trace the cable to it's source. JMO
westend
Explorer
Aug 26, 2014
A $2.00 roll of colored tape will take away a lot of fear and anxiety. I like to use Red as my positive (+) phase marking schedule. I know it's beyond most hobbyists but shrink wrap is even a better solution and can't be removed by an RV technician without a knife.