Battery dies after 1 mile

[Fairtax4me]

Ok that cart should have an OBC, which is what controls the charger.
Which should be either a grey or Black square on the aluminum mounting plate behind the batteries. The main negative cable for the pack needs to go through the hole in the OBC. Make sure the cable goes through the hole, and make sure that is the Only cable connected to the pack negative. The negative cable has to go through that hole for the OBC to read the pack properly and charge properly.

[roxy32]

It goes through the hole, but there were 2 other small cables hooked to the terminal. I took them off and charger would not kick on, put them back on and it kicked on.

[Fairtax4me]

That's not a good sign. Need to follow those other wires and find out what they go to. That usually means the OBC has been bypassed. Whether that's because it failed, or because of some other problem we'll find out when you figure out where those wires go.

If the wires go behind the aluminum cover, You can access the OBC and controller from underneath by jacking the cart up and putting it on jack stands. There is a plastic splash shield that covers the controller and OBC you may have to remove if it's not already gone.

The other option is to remove the center batteries and take out the Torx screw in the top of the aluminum cover, then the cover should lift up a little and pull it forward to get to the OBC on the back side of it.

Take pictures of where those two wires go and post them here if you can.

[roxy32]

golf cart wiring.zip

[roxy32]

The red wires go to the lights and speakers, I disconnected the speakers
The black wire goes into a housing, I will get some pics

[roxy32]

The black wire in the yellow connector is the other one attached to the battery

[Fairtax4me]

Can't see much but what I can see is that someone has disconnected the charge receptacle negative from the oBC, and ran it straight to the pack negative. Since the receptacle negative does not go to the OBC it has no way to determine if the batteries are actually charging, so it's shutting off too early.
That may mean the OBC has failed, but you'll need to hook it back up the right way first and test it.

From wire loom with the Grey wire and the 10awg Black wire. That Black wire is the receptacle negative and comes straight from the charge receptacle. Cut that smaller wire section off, and connect the 10awg Black wire to the with the single spade terminal in the white plastic connector. That is the negative going to the OBC. This is where those two wires Should be connected from the factory.
Connect those two, and totally remove that section of smaller black wire that goes to the pack negative. That is not needed.

Can you tell what the red wires on the pack negative goes to? I'm guessing either lights, or voltage reducer. Either way, it should not be there because the OBC can not account for the energy used by whatever that is hooked to. For right now, unhook that, and leave it unhooked.

Reconnect the pack negative, then plug the charger in and see if it works.
It needs to turn on, and the amp needle should go up to near the top and stay up there.
If the charger doesn't turn on, or the amp needle doesn't go up then the OBC has failed and needs to be replaced, or you can bypass it and get a smart charger.

[roxy32]

Did as instructed, charger went to about 13 out of 15 and after an hour or so dropped to 10 and has been there for 3 hours.
unplugged charger and checked voltage 8.89 on the first 3 and 8.69 on last 3 should I keep charging?

[Jake_Daddy]

Keep charging you probably could go all night and not hurt yours if they are dead after a mile which means they are shot or were not charged up worth a ****. You can’t get a good reading as soon as you take the charger off they need to sit for a while 12-24 hours to show you what they are really settling at. Since it sucks to wait 12 hours to recheck I would let the charger run overnight then toMorrow take a quick run up and down the street wait 15 minutes or so then take a volt reading for pack and individual batteries.

When my charger automatically shuts off it has to sit for about a day before it reads what’s considered 100% voltage. This is from what’s called surface charge which is kinda a residual high voltage your batteries will have right after charging.

[Fairtax4me]

I would leave it off the charger for the night, plug it back in tomorrow morning when you're gonna be around to kinda monitor it. It sounds like it's doing as its supposed to, but we still don't know if it's working properly or if it wasn't working before just because someone was monkeying around and fudged over the wiring. You'll want to keep an eye on it and make sure the OBC drops the current down again after a few hours around 10 amps it should drop down to about 5-7 amps, and then it will probably spend a few hours at around 5 amps before it finally shuts off. The entire charge cycle could take 16 hours. It may not take that long, but those batteries were pretty run down and they're gonna take quite some time to reach a full charge.

During charging you might see pack voltage as high as 65V for a 48v pack. Around 60 - 62v is typical for most packs, and the voltage will taper down to around 55-58v as the pack nears a full charge.
About 12 hours after charging with the pack at rest, you should see around 50.9v.