Proper Battery Wiring Configuration

That can be confusing. Some are hooked + to - on some series to make a 24 volt system (military etc.) I pulled up a page (this is the link) not as a spam, but to show different wiring diagrams. http://www.advancedenergysolution.com/Resources/diagrams.htm

(notice the difference for the 4- 6's in the 12 and 24 volt system.)

I would say the best advice would be to get someone to check it or call the service dealer and ask them before something is fried or someone gets hurt.

 

re-checked/tightened all connections and also looked at another truck like mine, but a 94. all connections seem to be correct so i tried starting the truck (no sparks).

as the engine was cranking smoke started to come off of one of the negative posts, which has a single white wire connected to it. there are a total of three white wires (about 8 or 10 gauge), one is connected to a negative post while the other two are connected to the positive post of the same battery. i have re-connected them the same way they came off. i have no idea what these wires are for. the other truck i looked at had three wires too (although not white). on the other truck 2 wires were connected to a positive post while the other wire was connected to the frame.

could the one white wire connected to the negative post actually need to be connected to the frame instead?

i hope this works...

 

Something does not look right to me. Are you sure the batteries are in the right direction? Looks like the pos from the truck is hooked up to the ground if I am looking at that right. Also I am not sure about those 3 wires. To me they look like they have been hot. It looks like a lot of brown on them.

 

The more I look at that I am not sure. The closest battery looks like a negative symbol - on the right side. Maybe it is just a smudge tho and not a negative sign.

 

it is just a smudge in the photo...

under each positive cable the battery has a red plastic pad as part of the battery. i know the positive side of the batteries were on the side of the battery box closest to the frame rail. (positive battery cables are too short to be any other way) in the foreground of the picture you should see one of the disconnected negative battery cables.

it seems, even thought the truck has four batteries, the truck is using 2 sets of dual batteries. does it matter if the positive cable is connected to the positive post of one battery and the negative is connected to the negative post of the other battery? (question make sense?)

also, where does the ecm get its power from?

i have been thinking about trying to start the truck without the 3 white wires connected (this will have to wait until next week)

 

assuming that everything is connected correctly and tight, and with the negative cable heating enought to produce smoke i would be there is a bad ground somewhere.

my backhoe which has a very simple wiring system was turning over real slow and the negative cable got hot enough to start melting the rubber and even after cleaning all the connections it was still getting hot.

I finally had enough and added another ground from the battery to the block and the problem was solved.

as far as the ecm if it is the same as my truck it will be one of the white wires that power it.

 

would grounding to the frame be ok?

based one this it would be a bad idea to try and start the truck with out these connected? (of course assuming these white wires are the ones powering the ecm)

 

My guess is the arcing you saw was when you put that one positive wire on the negative terminal. When you hit the starter, it tried to ground the entire system to the wire that is near the negative but not connected. Thus making me wonder what condition the rest of the electronics are in. Your attempt to save you money may have just cost you.

Please take a photo of the other end of batteries.

 

He said he had the negative cables disconnected in the pics.

 

Looking at it now makes me wonder as if the 3 wires groupe were intended to be wired in the middle. Thus giving him one set of batteries for a inverter and other set for the starter?