Low battery light dimly lit, warm batteries...why?

[Fairtax4me]

What is the serial Number for the cart?
What controller do you have? Exact model number would be most helpful.
The battery light is controller by either the OBC or the controller depending on production, that cart could have had either setup, so we need to know exactly which controller to know for sure.

Dimly lit suggests a wire problem, or modification to wiring due to a different controller being installed. (Alltrax/Navitas/etc)

Batteries will get warm during heavy use and possibly during charging depending on charge rate and depth of discharge.

The battery % displayed by the summit II will be innaccurate until it has done about 15-20 full charge cycles. That number is averaged out over time and the charge has to have multiple data points from charge cycles in order for that to be closer to the actual state of charge. Don’t try to rely on just that number to determine pack health.

[Wakko47]

Fairtax, thanks for the tip on the Summit. I did get it used, so it's not going to be accurate then. I tried to delete the data on it, but so far it hasn't worked.

Cart is a '14 JF model. I'm not sure which controller is in it, honestly. When I bought the cart, the dealer advised that it had a high speed motor in it (haven't verified this) and that otherwise it was stock, yet the cart does 28mph on stock diameter wheels. I was going to wait until I redid the cables before pulling the batteries out to check the controller, but I suppose it's worth checking now. I'll do it when I return from work.

[Wakko47]

Ok, I got it apart and found the stock controller. Interestingly, the water level seems low. All the cells are covered but I filled them about 5-6 weeks ago and they’ve lost water for sure. I have the stupid water fill system that I’d like to get rid of but I manually added water last time. Anyway, no smoking gun that I see. I will likely take the rest of the batteries out while I have it apart and clean the battery bucket up some. I wish I had the new cables so I don’t have to do this again.

[Fairtax4me]

So you should have had an ERIC charger original to that cart. The ERIC charger will boil the batteries dry in a few months of normal use if the charge algorithm in the charger is not correct for the batteries. That can be updated, but not much point now since you have the Summit II.

Make sure you use the Charger Connect app and pick the correct charge profile to match the batteries you have so the Summit II will charge them properly.

Ditch the battery light altogether, get a digital voltmeter to put in the dash in place of the battery light.

[Wakko47]

Yes, I have an ERIC but unknown profile. The Summit is correctly set to the Crowns. I’m building identicalish custom dash panels for this and my DS, which will include, among other things, pack voltage displays. Other than cleaning and topping off with distilled water, is there anything I should do with these batteries while they’re out? What triggers the battery light to begin with?

[CCNorth]

Originally Posted by Wakko47

Other than cleaning and topping off with distilled water, is there anything I should do with these batteries while they’re out? What triggers the battery light to begin with?

Check each batteries posts to be sure none are loose or show signs of overheating, i.e. melting. Be sure no battery is bulging on the sides.

Don't forget to check the sp gravity of each cell, as suggested by PingEye3.

Check the resistance of each of your battery cables. Your ohmmeter should indicate near zero resistance.

The OBC and controller trigger the battery light. Since you don't have a OBC, well....... see the post by FairTax4Me.

[Fairtax4me]

On your cart the controller commands the battery light on/off. I’m sure it has some sort of complex algorithm to determine battery pack SOC, but nobody other than Curtis really knows what those parameters are.
It probably has something to do with pack voltage Vs operation time since last charge, etc.

As I said before, being dimly lit would suggest to me a wiring problem, but knowing it has the stock controller, it could also be a problem in the lamp driver circuit of the controller. Or someone has been messing around with wiring in the dash and has wires crossed with the lamp circuit.

An exact reason could be narrowed down somewhat easily with the correct wire diagram for your cart, and checking voltage drop across the lamp, then disconnecting the wires for the lamp at the controller.
IMO it’s not worth bothering over. Installing a digital meter and learning to understand what voltage constitutes a low SOC is a far better solution than relying on a lamp that may or may not work properly. Remove it, problem solved.

[Wakko47]

CC and Fairtax, very informative responses, thank you. I suspect that the ERIC boiled the water in the batteries, causing them to go low, creating this issue. I'm waiting on my cell tester to arrive so I can test all the cells, refill the batteries, install the new caps (dump the self watering garbage) and reinstall all of the batteries. I'm probably two weeks out from the new cables, but I'll check the ohms resistance like suggested (why didn't I think of that??) in the mean time. I was in the dash once already to swap out the original lock cylinder with a Harley one, and someone was in there before to install a USB bank, but the wiring seemed good and not hacked.

[Sergio]

Can You tell where the wires from the USB bank goes?

Are there any wires connected to any battery post other than pack positive and pack negative?

The battery LED in the ERIC controller is a dedicated positive drive and it should not have dim light state.

Do You see anything connected to either wire in the LED light or to the optional black/yellow negative wire in the dash?

[Wakko47]

I'll double check the answers to your questions when I get home, Sergio. The dim light is on the dash, not the ERIC charger...that just showed FAULT. I'm not sure where the USB bank is tied into, I had anticipated tracking that down when I installed the aftermarket lighting and speedo.