New Batteries, Won't Hold a Charge

I have a 2001 GEM 2 seater with 9 month old deep cycle batteries. I can’t even get through 18 holes of golf now. The cart drains fast and once it hits 60%, it goes real fast.

What happens around 40% is the cart shuts down, error code -11 appears and I have to take my foot off the accelerator and turn off/on the GEM.

All connections look real secure, no battery corrosion.

Any thoughts, else I need to take it in.


hi Midway… sounds like maybe not all your batteries are charging… check each one after charging your car… they should all read the same… about 13.2 when charged if you have a bad battery it will pull the pack down


This is a common issue. If the power to the controller is interrupted for a fraction of a second, the system resets and senses your foot on the throttle. This causes the -11 alarm and exists to prevent a runaway if the GEM is turned on with the throttle stuck. First, be sure the floor mat is not getting under the pedal. Then, be sure your parking brake interlock switch is not loose. Both of these conditions will cause nuisance -11 errors. Test each battery accurately after charging. Look for small variances in voltage between the batteries.


I too was getting -11 errors when I first got my (used) 01 GEM. I ended up taking the throttle assembly apart and cleaning up the switch contacts and using WD40 to lube up everything so it was smooth. I then took the rubber floor mat out of he car and cut a wider allowance around where the foot pedal was so that under no circumstances could it move sufficiently to get under the lip of the throttle assembly. After doing these, my -11 errors went away (except for the one time I hit a pothole so hard, it mechanically disengaged the contactor which triggered a -11 error once the contactor re-engaged!!).

None of that explains the rapid power loss however and I agree with Bob that the most likely explanation is a cell in a battery that’s shot and would follow his suggestion to diagnose. I’d also get a battery hydrometer and test each individual cell if I found one battery that was weak. I found from experience that one “dead” cell in one battery will eventually tank the whole string. I’m now “RELIGIOUS” about checking the water levels in my FLA batteries every month and topping them off if necessary. A set of good batteries is far too expensive to replace because I let a cell go dry from inattention. Since I have FLA batteries I can pull off the fill caps and check water levels. You don’t mention what technology you have and if it’s AGM or GEL, you can’t. I also am passionate about using industrial grade (I personally use Trojan FLA) batteries in a GEM vs “marine deep cycle”. IMO “marine deep cycle” batteries are a waste of money in this usage and won’t last more than a year or two before needing replacement.


my neighbor up the road who asks my opinion ona GEM car problem then goes in the opposite direction on my answer… usually it’s something I’ve tried or done… his latest problem has been with batteries… we both have '05 cars… he tried flooded batteries and the car had range and over heating problems… I said go to the Deka and where he could get them for $200… he found his for $100… still a problem… now his kick is COLD CRANKING something… my batteries are doing well… his new ones are still giving him fits… I don’t see a cc? on my battery it’s the 8G31 Solar… I drive he doesn’t


All, thanks for the feedback. I’ll start by testing easy battery on full charge as Bob suggests. Thanks again.