36v reducer hook up with existing wiring

[Jblack]

OK gents another sparky question. I want to add a 4 wire 36V reducer to the wiring harness. Currently the cart has the accessory wiring harness that feeds the lights, which includes the +12v fuse block and 3 position keyed switch.since this harness feeds off the last two batteries in the pack I want to update it to the reducer. Remove the old green wire to the fuse block and replace with the yellow
The question I have in 12v ground connection on the reducer. Can I just use the existing ground in the harness that ties into B-? This is a 10 or 12ga wire. Or do I need to run that ground back to the reducer 12v-?

[handtools]

The way I would do it would be to hook the reducer 36v input wires to the battery pack as you show them then hook the reducer 12v output wires to the harness wires, yellow to green as you show and black to black, after removing the green and black from the batteries!

[clnorris75]

That light kit has a 36v connection as there is a red wire at your B+. The green wire simply reduces the voltage down to make it 12v to power the fuse box where the harness wires connect and power the lights. The hot wire for the lights is the blue/white wire at the fuse box. There are two blue/white wires in your dash from the harness. One is negative and the other is positive. These are the two that connect to your key switch to turn the lights on.

The Orange wire in the fuse box is for the horn and the red one is for I believe flashers. I believe they are connected regardless if you actually have those items installed at least they were in mine and I have neither. It was for if you wanted to add those items later or upgrade.

I am doing the same thing except I am running the blue/white that was in the factory fuse box to my new fuse box my reducer powers and using the existing ground from the light wiring harness to B-. Now that you have a reducer, the factory fuse box, B+ red wire and the green wire will be eliminated and the blue/white wire that was connected to the fuse box will be wired to your reducer to power the lights.

As with any electrical project please confirm all connections with a voltmeter prior to powering on.

[handtools]

Upon closer inspection of the diagram I see the red B+ powers the SOC meter and gets it's B- from the harness black wire. So disregard my previous comment about removing that wire from the batteries as the meter wouldn't work. To answer your original question I believe you can combine those two black wires from the reducer and connect them both at B-. And yes, always confirm voltages with a meter.

[Jblack]

Thanks for the responses! I'll combine the 12v ground back to the battery pack, leaving the existing ground as well. I figured it was straight forward, but I wanted confirmation. I have much respect for the little angry pixies and I don't like when they try to smoke you out

[Jblack]

So I hooked up the reducer 36v+wire, then hooked up the main B- cable. Next up was the Acc harness ground. All's good.Next up was the 36V ground wire from the reducer and I got a sizable spark! I then tried the 12v reducer ground and the pixies jumped the gap with a nice blue spark again.: shock:

So I'm not sure what's up. Should I be getting a spark when I hook up these reducer grounds? Tell me if I'm just being a sissy

[handtools]

My reducer sparks pretty good when you make the last connection also.

[Cobra,1]

Reducer when connected will spark as reducer always draws a small amount on batteries even with accessories off. Mines does the same. Draws 1 amp or less depending on reducer.
Unless reducer has a key on function that turns on(energizes) reducer only when key is turned on, you will get spark when connecting.

[Jblack]

thanks guys!