2015 GEM es moves very slow

I have an GEM eS that moves very slowly in forward and reverse. I recently put 6 new T1275 Trojan batteries in the cart. I had to work through setting a new algorithm in the Delta-Q charger. The previous owner told me that it moved very slow. When I got the cart the batteries would not charge greater than 4.7% go I replaced them. I did see an 82 code pop up on the display very briefly. I noticed that there is a burning type smell after running a few minutes. The motor is warm to the touch. I checked the speed sensor sensor but it looked good. I have ordered a new one from ebay. I tried pumping the accelerator multiple times with the key off. I pulled the plug on the controller and blasted with compressed air. I also blasted the motor with compressed air. I jacked the front wheel so I can run in place. Made no difference. I’m trying to follow recommendations mad to MB1137 by ASSYREQUIRED in another thread. Please help me with the next steps. I do have a volt meter and can work at a slow pace. Any and all recommendations are appreciated.

Are batteries charging up fully?

If so, lift up your ass end and check for dragging brakes once you release the parking brake. That could do everything you describe

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Oh Man! He is following some old advice from me from an old thread?
I am somebody now!!!

Do you have any history of this car?
Has it been sitting for a while?
What year is this car?
What motor is this?
Along with the odd smell, is it making any deep down grumbly noises when you try to accelerate?

If my frontend is off the ground, and my front wheels move slowly, why would the back nd have and effect?

Do you have any history of this car? I have the title and the previous owner told me that it ran very slow.
Has it been sitting for a while? I feel that the car has been sitting for a while.The batteries would not get more than 4.7v when charged overnight.
What year is this car? 2015 GEM eS
What motor is this? PART NO. GU3-4002 2412501, VOLT DC 72, SERIA NO. 5390, RATING AU2500 11/22/16
Along with the odd smell, is it making any deep down grumbly noises when you try to accelerate? No not that I hear in the driver’s seat

In post 1 you said

batteries would not charge greater than 4.7% so I replaced them.

First, you should scrounge up a meter so we can check voltages directly to aid in diagnostics and verify that you installed the new batteries correctly.

You should be charging the car with the Main Battery switch ON, and verify that the Charger is functioning properly by looking at it’s built in display. Look for the charger under the hood of the car. Don’t pay any attention to what you are seeing on the Dash Pod display at the moment.

When the car is plugged in to charge what lights do you see on this display?
Also- when the car is plugged in, you will see a yellow charge cord light on your dash and the dash will show an animated battery with a filling battery. This does not really prove that everything is working properly.


Running the car in place will get it exercised, maybe clean off the comms if you get lucky. If the car sits for a while there is a chance the brushes are stuck and not making full contact with the comms. You might be able to unstick them with some light taps on the end cap with a hammer. If they are REALLY stuck bad then your motor will need to be serviced.

If the front wheels spin up real fast when the front end is jacked up then as jrjava was suggesting the back brakes may be locked up and slowing the car down. That tends to happen too. Jack up the back of the car and make sure the rear wheels move freely when the brake handle is down.

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@vanna white

I mean @nav

Could I buy some paragraphs and line breaks? Your ■■■■ is really hard to read.

The display shows charging to 99 starting from 81 yesterday. A green light appeared on the charger when done. I just checked 76.8V total battery pack. The front wheels move very slowly when off the ground just as they do while on the ground.

I experimented with my cart today. I first charged it from 91% to 99%+. I still have the front on jacks. I put a chalk mark on a tire that I could see from the driver’s seat. It was taking 11-12 seconds to complete a 360 degree revolution whether in forward or reverse. after 10 +/- minutes it completely stopped turning. the motor head was hot to the touch. I did smell the burning type scent from the motor. Is it time to remove the motor for service? Could the controller be causing this situation? I do have a 2015 GEM e2 as a spare, but I fear it is in worse shape (my next project maybe).

You previously saw a -81 but did that go away?
Does the display on your dash pod show any other. numbers or does it show the speed? (0 when stopped)

Does it show a little green turtle or temp symbol?

Yes- Remove motor. Pull off that grill cover and show us a pic of what you see in there.

Depending on what you find- as a test, I may suggest to pull the other motor out of your e2 and stick it in this car.

76.8v for the pack sounds a bit low. What are these batteries and how long ago did you replace them?

The 81 code just flashed on the screen for a second the other day. Not today. No other codes appeared. No turtle or temp lit up. Only emg brake light when hand brake is on. The batteries are Trojan T1275 's installed last month.

Nick Valsamakis

Can you post a pic of the cables that come off the controller and go to the motor?

Both ends. The controller, then the motor connects.

Here are pictures


Ok- thanks for humoring me. Those look correct. I thought I was on to something.

Now- see if you can figure out how to remove that shiny cage/grille with diamond shaped holes and get a couple of pics of what it looks like in there. Use a flashlight if it is too dark or see how your phone light works out.

The commutator is all the way down in near the middle and looks like a bunch of piano keys. You will see the brushes in paired racks pointing in towards and rubbing at the comm keys.

Is this what you wanted?

Nick Valsamakis

Any idea why those brush springs are not wound up and placed pushing down on top of the brushes?
It won’t work correctly without them properly in place.

And if that is the commutator below the loose brush springs that commutator is charred and is in BAD shape.

Nick Valsamakis

maybe someone did a brush replacement and failed… Not a good setup.

Ding, ding, ding!!!

As dougl pointed out, those springs in your pics were never released from their service positions. Depending on how many are like this it would TOTALLY explain what is going on.

If you carefully (one at a time, hold on to it tight) move it towards its mate and it will come off that tab and unwind a bit, so the hook of the spring will land on top of the brush. It should look like your first pic. Do this to both brushes.

There are 4 sets of these brushes all the way around the motor. You might not be able to reach one set due to lack of room down there.

BUT (and its a big but) Your comms are also extremely scorched because the lack of good brush contact probably caused some big blue arc down in there. That might have been the smell (ozone).

You could release all springs(making sure the rolled foot lands on a brush) and there is a slight possiblilty that it will clean itself up a little, but I doubt it. Having dirty comms is a good way to blow up the controller.

It would be really nice if you could take this motor out and get it serviced.
This is a great motor and if you treat it well it will pull you along nicely.

Where are you located again?

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I’m in Aberdeen, Mississippi. There’s a business in Columbus, MS about 25 miles away that rebuilds motors for big plants in our area.

Nick Valsamakis