# Acceleration problem **URL:** \ **Category:** EV Small Talk\ **Tags:** blog\ **Created:** [December 25, 2021, 11:04pm UTC](https://community.electricforum.com/t/acceleration-problem/23151 "2021-12-25T23:04:40Z")\ **Posts on this page:** 18\ **Page:** 1
**Author:** ![Camerharter](https://avatars.discourse-cdn.com/v4/letter/c/f0a364/32.png) [@Camerharter](https://community.electricforum.com/u/Camerharter)\ **Post date:** [December 25, 2021, 11:04pm UTC](https://community.electricforum.com/t/acceleration-problem/23151/1 "2021-12-25T23:04:40Z")
I have a 1999 E2 gem car. 48 volt. I can accelerate until I push the pedal all the way down then the motor will shut off. I can fully throttle going in reverse and I’m fine. ---
**Author:** ![Inwo](https://yyz2.discourse-cdn.com/flex030/user_avatar/community.electricforum.com/inwo/32/1067_2.png) [@Inwo](https://community.electricforum.com/u/Inwo)\ **Post date:** [December 25, 2021, 11:34pm UTC](https://community.electricforum.com/t/acceleration-problem/23151/2 "2021-12-25T23:34:46Z")
What error code? Shuts down with speed or throttle position? ---
**Author:** ![Camerharter](https://avatars.discourse-cdn.com/v4/letter/c/f0a364/32.png) [@Camerharter](https://community.electricforum.com/u/Camerharter)\ **Post date:** [December 26, 2021, 12:11am UTC](https://community.electricforum.com/t/acceleration-problem/23151/3 "2021-12-26T00:11:58Z")
Throttle position. I don’t have a code. ---
**Author:** ![Inwo](https://yyz2.discourse-cdn.com/flex030/user_avatar/community.electricforum.com/inwo/32/1067_2.png) [@Inwo](https://community.electricforum.com/u/Inwo)\ **Post date:** [December 26, 2021, 1:06am UTC](https://community.electricforum.com/t/acceleration-problem/23151/4 "2021-12-26T01:06:29Z")
That’s a strange one for me. Same throttle position works in reverse. ---
**Author:** ![Inwo](https://yyz2.discourse-cdn.com/flex030/user_avatar/community.electricforum.com/inwo/32/1067_2.png) [@Inwo](https://community.electricforum.com/u/Inwo)\ **Post date:** [December 26, 2021, 1:08am UTC](https://community.electricforum.com/t/acceleration-problem/23151/5 "2021-12-26T01:08:53Z")
Test the motor by switching the field wires. It will move car forward when in reverse. We will see if motor runs both directions. ---
**Author:** ![Camerharter](https://avatars.discourse-cdn.com/v4/letter/c/f0a364/32.png) [@Camerharter](https://community.electricforum.com/u/Camerharter)\ **Post date:** [December 26, 2021, 4:10am UTC](https://community.electricforum.com/t/acceleration-problem/23151/6 "2021-12-26T04:10:28Z")
Yes. I’m puzzled I’ll try switching field wires. Thanks ---
**Author:** ![Inwo](https://yyz2.discourse-cdn.com/flex030/user_avatar/community.electricforum.com/inwo/32/1067_2.png) [@Inwo](https://community.electricforum.com/u/Inwo)\ **Post date:** [December 26, 2021, 5:08am UTC](https://community.electricforum.com/t/acceleration-problem/23151/7 "2021-12-26T05:08:22Z")
@AssyRequired any ideas on this one? Always a possibility that it’s batteries. 90% of the time it is. 🙂 ---
**Author:** ![AssyRequired](https://yyz2.discourse-cdn.com/flex030/user_avatar/community.electricforum.com/assyrequired/32/7621_2.png) [@AssyRequired](https://community.electricforum.com/u/AssyRequired)\ **Post date:** [December 26, 2021, 5:12am UTC](https://community.electricforum.com/t/acceleration-problem/23151/8 "2021-12-26T05:12:08Z")
No codes? and display is acting normal?(showing speed) Or the display is not working? (dark) Is the main contactor clicking out? Put a meter on your controller and monitor the volts it is seeing when you accelerate. What is the last V you see before it trips out? Don’t crash into anything. Can you repeat this by doing a brakestand test? ---
**Author:** ![Inwo](https://yyz2.discourse-cdn.com/flex030/user_avatar/community.electricforum.com/inwo/32/1067_2.png) [@Inwo](https://community.electricforum.com/u/Inwo)\ **Post date:** [December 26, 2021, 5:17am UTC](https://community.electricforum.com/t/acceleration-problem/23151/9 "2021-12-26T05:17:37Z")
I wasn’t paying much attention, sorry. I know nothing about the 48v model. Not even if it’s a sepex or series motor. 😣 ---
**Author:** ![AssyRequired](https://yyz2.discourse-cdn.com/flex030/user_avatar/community.electricforum.com/assyrequired/32/7621_2.png) [@AssyRequired](https://community.electricforum.com/u/AssyRequired)\ **Post date:** [December 26, 2021, 5:21am UTC](https://community.electricforum.com/t/acceleration-problem/23151/10 "2021-12-26T05:21:52Z")
I’m just guessing here too. How different are the 48V cars? It’s just where I would start looking. ---
**Author:** ![Camerharter](https://avatars.discourse-cdn.com/v4/letter/c/f0a364/32.png) [@Camerharter](https://community.electricforum.com/u/Camerharter)\ **Post date:** [December 26, 2021, 9:33am UTC](https://community.electricforum.com/t/acceleration-problem/23151/11 "2021-12-26T09:33:34Z")
I was thinking about that. Thee batteries are about a year old but might have a bad cell In one. I’ll check that also. Thanks ---
**Author:** ![Camerharter](https://avatars.discourse-cdn.com/v4/letter/c/f0a364/32.png) [@Camerharter](https://community.electricforum.com/u/Camerharter)\ **Post date:** [December 26, 2021, 1:47pm UTC](https://community.electricforum.com/t/acceleration-problem/23151/12 "2021-12-26T13:47:06Z")
Thanks. I’ll look at that also. ---
**Author:** ![Camerharter](https://avatars.discourse-cdn.com/v4/letter/c/f0a364/32.png) [@Camerharter](https://community.electricforum.com/u/Camerharter)\ **Post date:** [December 26, 2021, 1:52pm UTC](https://community.electricforum.com/t/acceleration-problem/23151/13 "2021-12-26T13:52:37Z")
Yeah. It’s actually a trans gem cart. The first carts to come out. No screen, no codes. I’m checking on batteries to make sure no bad cells. I’ll also check voltage. Thanks ---
**Author:** ![AssyRequired](https://yyz2.discourse-cdn.com/flex030/user_avatar/community.electricforum.com/assyrequired/32/7621_2.png) [@AssyRequired](https://community.electricforum.com/u/AssyRequired)\ **Post date:** [December 26, 2021, 2:13pm UTC](https://community.electricforum.com/t/acceleration-problem/23151/14 "2021-12-26T14:13:39Z")
Ah! From a remote problem solver view- the response of > I don’t have a code. is WAAAAAAYYY different than not even having the ability to view a code. It tends to allow a bypass of a bunch of things that should be otherwise be checked. I’m still sticking with batteries as a first thing to check tho- I’m a little puzzled that the cart actually shuts down with this issue. Normally a low V will just go slow and if it drops below it’s lower threshold it won’t bother starting up again after power cycle. Do you know what controller is in this cart? ---
**Author:** ![Gem\_e2](https://yyz2.discourse-cdn.com/flex030/user_avatar/community.electricforum.com/gem_e2/32/1849_2.png) [@Gem\_e2](https://community.electricforum.com/u/Gem_e2)\ **Post date:** [December 26, 2021, 2:19pm UTC](https://community.electricforum.com/t/acceleration-problem/23151/15 "2021-12-26T14:19:50Z")
old 48v schematic ![48volt](https://canada1.discourse-cdn.com/flex030/uploads/electricforum/original/2X/f/f13b87140e066a0b648d0a8ba80f78561f62b121.jpeg) ---
**Author:** ![AssyRequired](https://yyz2.discourse-cdn.com/flex030/user_avatar/community.electricforum.com/assyrequired/32/7621_2.png) [@AssyRequired](https://community.electricforum.com/u/AssyRequired)\ **Post date:** [December 26, 2021, 2:35pm UTC](https://community.electricforum.com/t/acceleration-problem/23151/16 "2021-12-26T14:35:56Z")
Thanks Ge2. Way to pull a rabbit out of a hat! Unless the cart was changed over to something else by a PO in the lase 22 years… It looks like factory setup is a Curtis control and a manual direction sw? This blows my theory about the controller treating FWD and REV with different parameters in it’s programming. ---
**Author:** ![Inwo](https://yyz2.discourse-cdn.com/flex030/user_avatar/community.electricforum.com/inwo/32/1067_2.png) [@Inwo](https://community.electricforum.com/u/Inwo)\ **Post date:** [December 26, 2021, 3:34pm UTC](https://community.electricforum.com/t/acceleration-problem/23151/17 "2021-12-26T15:34:52Z")
Reversing field is still a valid test of motor circuits. ---
**Author:** ![Camerharter](https://avatars.discourse-cdn.com/v4/letter/c/f0a364/32.png) [@Camerharter](https://community.electricforum.com/u/Camerharter)\ **Post date:** [December 27, 2021, 11:24am UTC](https://community.electricforum.com/t/acceleration-problem/23151/18 "2021-12-27T11:24:21Z")
I put the batteries one at a time on a charger. I found that one battery was bad. It just wasn’t getting enough voltage. Thanks everybody. I do appreciate all your help.