Ezgo TXT jumping severely under light acceleration

[jaroniles]

I have a 2004 ezgo that i put a alltrax xct kit on in august 2020. Last year it started acting up and when i press the pedal it starts jumping and jerking really bad unless i slam it down. The large diode was cracked in half, so i replaced that and no change. But yesterday i put new 2 gauge cables on and it was perfect, for one day. It started jumping even worse than before today after it got a full charge.
I ordered the XCT400PDS
2004 ezgo txt 48V

Any help would be appreciated! thank you!

[kgsc]

Hook up a computer to the controller and see what the throttle is doing when pushing the pedal. If it is jumping around check the wires first then check the ITS for damage.

[jaroniles]

forgot to add it only does it in forward, reverse is fine

[Tom47]

Just a thought:

If your motor is original, it might have bad brushes or burned brush holders. That would account for it jumping in forward but not in reverse.

Reverse is not used as much so the brush wear will be less noticeable as the motor runs in reverse. If one or more brush holders are burned, it will permit the brush to slop around in forward, but not in reverse.

Also, putting the new motor cables on would reorient the terminal slightly which could improve drivability for a while. I would pull the motor and check it.

Good luck with fixing this problem!

[scottyb]

Assuming it is a PDS cart and the problem is in one direction only we know the throttle signal is okay and we know the motor is okay, since both of those components work the same in both directions.
1. Swap the wires on the F&R switch top to bottom, this will tell if the switch is a problem. If not then put it back and see if just messing with the connections fixed the problem.
2. Swap the F1 and F2 wires at the controller. The controller has 2 halves or 2 controllers within, one for each direction. If swapping F1 and F2 reverses the direction of the problem the controller may be faulty. If the problem follows the wire (F1 or F2) THe problem may be a short in the wire at a point where it goes around the battery frame upright behind the controller.

[jaroniles]

Originally Posted by scottyb

Assuming it is a PDS cart and the problem is in one direction only we know the throttle signal is okay and we know the motor is okay, since both of those components work the same in both directions.
1. Swap the wires on the F&R switch top to bottom, this will tell if the switch is a problem. If not then put it back and see if just messing with the connections fixed the problem.
2. Swap the F1 and F2 wires at the controller. The controller has 2 halves or 2 controllers within, one for each direction. If swapping F1 and F2 reverses the direction of the problem the controller may be faulty. If the problem follows the wire (F1 or F2) THe problem may be a short in the wire at a point where it goes around the battery frame upright behind the controller.

Alright scotty, you’re a genius, i swapped the F1 and F2 at the controller and now when going forward the problem is pretty much gone but when going in reverse it’s a little jumpy now, so that would mean that there might be a problem with the controller? or should i just replace all the wires with new ones, hook it back up how it was originally and see if that fixes the problem?

(worst case if it doesn’t fix it i could just leave it swapped and let the problem exist in the less used direction right?)

[scottyb]

Originally Posted by jaroniles

Alright scotty, you’re a genius, i swapped the F1 and F2 at the controller and now when going forward the problem is pretty much gone but when going in reverse it’s a little jumpy now, so that would mean that there might be a problem with the controller? or should i just replace all the wires with new ones, hook it back up how it was originally and see if that fixes the problem?

(worst case if it doesn’t fix it i could just leave it swapped and let the problem exist in the less used direction right?)

Since the problem followed the wire we should have a look at the F1 and F2 wires where they go around the battery frame. Remove the rear passenger side battery to make this inspection.

[DaveTM]

A few years back I had my cables wear through at the battery corner. All kinds of funky things occur when that happens. Now I have strategic zip tie placements to keep those cables from coming into contact with the battery housing corner.

[jaroniles]

so i rewired everything, every cable that involved batteries and motor got 2 gauge replacements. the issue is gone no more more jumping. i appreciate all the help!

love you bye