Newbie can't charge reliably

Hi all,

I just bought my first GEM. I have a lot of experience with golf carts (Club Cars in particular) but I don’t have any experience with (a) GEMs, (b) gel batteries, © battery banks larger than 48V. I don’t understand the behavior I’m seeing. I’d love some education:

(1) What should the pack voltage be when it is at 100% SoC? Currently my dashboard shows only 6 of 8 green bars lit, but using a volt meter I measured the pack to be 79.8 volts. (6x12 gel batteries). That seems high even for a pack that is at 100% SoC, so the fact that only 6 bars are lit makes it seem absurdly high.

(2) How should the charger behave during a normal charging cycle. I.E., should the dash gauge remain lit the entire time until it indicates 100%, or should the dash go blank at some point. My dash goes blank after random durations–sometimes a few hours (1 or 2), sometimes many hours (7 or 8).

(3) What would cause the charger to sometimes turn on and other times not turn on even though I’m following the same steps each time? Per the owner’s manual I plug the ac cord into the cart first, then the wall. (Even though the pack voltage is well above the 68V “safety” level, sometimes the charger will not start.)

(4) What causes the turtle icon to illuminate? Is it strictly some voltage threshold of the pack? If so, what voltage?

I’m hoping it is user error, and not some problem with the vehicle. Either way, it would be great to understand how charging is supposed to work.

Thanks in advance,


Well, #2 & #3 can be explained by the fact that the plug in the hood was loose and wasn’t always making a solid connection with the extension cord.

I’m still curious about #1 & #4.



1 Not an unusual number right after charging. Allow 4 hours for the surface charge to dissapate before reading. Charging voltage goes up to the high eighties and beyond depending on the algorithm.

4 Low voltage/percentage of charge. If your seeing this you are running way to far before recharging or your battery pack is worn out.

Best battery life is obtained by plugging in after EVERY usage.