EZGO 48V TXT battery troubleshooting help please!

[nmgoes]

Hi there- new to the forum; but have been reading and trying to learn from the previous threads.

I just purchased a used 2011 TXT. At full charge, it was slow up hills and maxed out on flat at 15 mph (the jerk I bought swore to me it would do 25 mph and is nowhere to be found now). Battery indicator read 3/4 full when I started on a golf game so I thought it would be fine. I tried to reverse up a steep hill and it wouldn't go! Then the cart started slowing significantly up the point where it would not carry the second passenger and I had to be towed home.

Water levels are fine. I charged it overnight and tested each battery this morning. Lowest battery read at 8.34V and highest read 8.6v. Pack registered at 54-55v. All after charging all night.

From what I described, does it sound like I have a bad battery? Any other areas I should check? The batteries are Trojans (6 x 8v). Pardon the ignorant questions- I am new to this and appreciate any insight.

Thanks!!!

[Sir Nuke]

nmgoes......we need a bit more information to get the picture right the first time.

1. What type drive system does your cart have, series or sepex? if you don't know, look at this treat and you can tell. http://www.buggiesgonewild.com/elect...en-system.html

2. make a list of the battery voltage for each battery. a battery pack in good shape shouldn't have that much difference, should be within .1 of each other.

3. Seeing as how you state that pack voltage was 54-55v (should be roughly 50.9).....they had not rested totally after charging.....you need to take all your readings after the pack has rested (not used) for 12 hours.

[nmgoes]

Thanks for the response Sir Nuke.

Based on the guide you posted, I have a Sepex.

You're right- I tested them right after I took it off the charger. I'll disconnect it tonight and let it sit overnight and retest tomorrow morning.

I had read on another post that the batteries should test around 9.3v individually- is that accurate? It didn't make sense to me that my batteries would test individually around 8.5-8.6 (with the exception of the one that tested at 8.34) but my pack collectively tested around 54. (8.4 x 6 = 50.4, right?)

For a 48V TXT, I noticed that the other 48v are faster than mine which made me wonder if my batteries weren't as potent. After trying to reverse up a very steep hill, it seemed to start the decline.

Anything else I should be checking on? I visually inspected my cables and it doesn't appear to have any cuts in the insulation that would allow for a grounding issue. There is a battery terminal with very slight buildup on it, but nothing major. I may clean those contact areas as well.

I welcome any thoughts and insights.

[yurtle]

I have eight 6 volt batteries, but 6.37/3*4 = 8.5 volts. Should be close. That would give you a pack voltage of 50.96, and I've always rounded mine to 51 volts, to make it easy to remember.

[Sir Nuke]

Originally Posted by nmgoes

Thanks for the response Sir Nuke.

Based on the guide you posted, I have a Sepex.

You're right- I tested them right after I took it off the charger. I'll disconnect it tonight and let it sit overnight and retest tomorrow morning.

I had read on another post that the batteries should test around 9.3v individually- is that accurate? It didn't make sense to me that my batteries would test individually around 8.5-8.6 (with the exception of the one that tested at 8.34) but my pack collectively tested around 54. (8.4 x 6 = 50.4, right?)

For a 48V TXT, I noticed that the other 48v are faster than mine which made me wonder if my batteries weren't as potent. After trying to reverse up a very steep hill, it seemed to start the decline.

Anything else I should be checking on? I visually inspected my cables and it doesn't appear to have any cuts in the insulation that would allow for a grounding issue. There is a battery terminal with very slight buildup on it, but nothing major. I may clean those contact areas as well.

I welcome any thoughts and insights.

Once you charge and let it rest the 12 hrs......each battery should be in the 8.5v range, give or take .1v. but it appears you may have one battery going south on you.

the other thing I would do, if you haven't in a good while, would be to take off each high current cable (one and a time) and thoroughly clean the connection and reconnect. but on the batteries themselves, remember not to over tighten them, as stock torque is only about 10 ft-lbs.

[JohnnieB]

Battery Maintenance 101: Lesson-1: Get rid of the LED bargraph type battery meter and replace it with a DVM type.
Those miserable bargraph thingies lie more than some politicians.

Attached is a SoC (State of Charge) vs Voltage chart for Trojan batteries.
The voltage shown is AT-Rest voltage. (IE: 12 hours after charging stops and 1 hour after discharging stops.)


You may have a battery failing under load or a bad cable/connection or some other issue(s), but finding out what the pack voltage is after a 12 hour rest is a good starting point.

Bad cables can look good. A quick check is feeling them after a hard run. They should all be about the same temperature and none should be more than lukewarm.

[nmgoes]

Thanks for the tip and for the chart- that helps me get an idea of what to look for.

I'll wait 12 hours overnight and try again tomorrow morning.

In the event I have 1 bad battery amongst 6, is it safe to replace only one battery and not the others?

What are your thoughts on 'refurbishing' Trojan batteries with those kits they sell on Amazon or Ebay?

[Sir Nuke]

Originally Posted by nmgoes

Thanks for the tip and for the chart- that helps me get an idea of what to look for.

I'll wait 12 hours overnight and try again tomorrow morning.

#1. In the event I have 1 bad battery amongst 6, is it safe to replace only one battery and not the others?

#2. What are your thoughts on 'refurbishing' Trojan batteries with those kits they sell on Amazon or Ebay?

#1. Yes you can.....but, how old are your batteries? the best thing to do would be, if possible, get a used battery that is the same make/model and age as your current pack. Otherwise, if you just replace it with a new one, it will attain the "age" of the pack.

#2. don't do it......its "SNAKE OIL"

[nmgoes]

Ok- so I unplugged last night around 6pm and tested this morning at 7am.

I have 5 batteries that register 8.5 volts within .1 volts of one another.

I have one battery that registers 8.3 volts (in the rear corner of the pack, away from the master ground and positive).

The overall pack registers at 51 volts (50.9).

My cart is a 2011- and the batteries are original to the cart.

Any thoughts?

Could that 8.3 be causing the problem? Any thoughts as to what I could try? Thanks for the tip on NOT doing the battery restoration kits, I'll stay away. I don't know where to get a used Trojan battery of the same age, etc.

I thought about taking off all the battery cables and replacing them with new ones.

I'm stumped, with all the batteries reading as they do, i don't know why 1) the cart is only maxing out at 15mph and 2) why going up a steep hill in reverse fried my remaining life and left me stranded when my battery indicator showed 3/4 full (i understand that those indicators aren't too accurate from a post here).

Thanks again.

[scottyb]

Connect the meter to the pack and drive uphill.... what is the starting voltage and what does the pack drop to under load? If it drops more than 5-6v you may have a bad battery . attach the meter to the suspect battery and redo the tests. If the suspect (or any individual battery) drops more than 2v under load it is bad.

I hope this helps