Jerking in fwd and rev does not drive

Hi guys, new to Gem carts. I have a 2016)
E4 that barely inches along and sounds horrible in either fwd or rev. With front tires off the ground the cart front wheels spin fast. Under load/on ground nothing. Do I have a bad motor?

Make sure encoder is plugged in solid. And encoder is not loose.
Flat 4 wire plug from motor.

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Yes it is 100 plugged in.

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I have a similar problem

Mine runs after i push it or spin the tires.

I am trying a new speed swnsor

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See if it’s the same with sensor unplugged.
It will also do that if motor is phased wrong.
Have any wires been disconnected?
Any other history?

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Nothing has been disconnected. Newer batteries.
Video of motor out.

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Are the brushes in the motor sliding freely?

I’ve been working on a motor where the brushes were seized solid and the buggy motion was jerky. I’ve freed up most of the brushes and now the motion is much smoother (though it might have been due to something else).

Forgot to ask. What error codes?

AC motor in the OP’s gem. They don’t have brushes.

Codes pop up on the dash panel? Controller had a green light no flashing codes.

Must be a Polaris problem then. What codes?

I’m not sure where to find the codes? The dash panel display here only has a wrench pop up when it’s acting up. I had the motor out yesterday and it is an a/c Mahle motor. Seemed like the rotor had some play in it and did not spin freely on the stator. Put the motor back in. Today it’s at least driving 5 mph. Before it starts bucking and just stops again.


Select with the button to display fault codes.

Sevcon errors clear when powered down. Look for code immediately after car bucks.

I did only wrench pops up.

Okay I have code 6?

Over current or ground fault.
All I can think of is to disconnect phase wires and meg them to frame.

I saw your video when you had the motor out. That motor only has one bearing on the far end and is supported on the spline end by the gearbox input shaft bearing.
It looked like what you were doing was perfectly normal. Your vid showed/sounded like you were moving it to the side far enough to catch the speed/hall sensor.

When your display is showing Veh Fault (and or the wrench) you should be able to scroll through them with the Mode button.

Found out how to get the fault code to display. Here is the code: 520518: 6

Same code.
You might try driving with phase wires disconnected. See if it throws an open circuit code.