04 DS Alltrax randomly won't go/jerky after stopping

[superfan86]

Friend has an 04 DS Sepex with a 300 Amp Alltrax. After driving for a period of time if your stop the cart jerks and won't move. After about 15-30 min the cart will start working again.

Symptoms and troubleshooting:
- This issue existed prior to the Alltrax, but is getting worse to a point that they can't drive it now.

- Alltrax is tuned correctly, but the cart caps out around 13 mph. I'd expect around 20-25 with this setup. It used to go faster.

- speed sensor appears good. Cart Regen brakes on rollaway.

- I have replaced the MCOR and it didn't improve.

- The batteries are 1 year old, test good, and are fully charged.

- see attached picture. The Alltrax reports low volatage (38v), but the pack voltage is reading almost no drop, above 50v at the same time.

I'm thinking the motor? Could this be solenoid?

[Volt_Ampere]

Sounds like possibly a failed solenoid if the Alltrax is seeing low voltage. I had that happen to me a couple years ago with similar symptoms.

[superfan86]

Originally Posted by Volt_Ampere

Sounds like possibly a failed solenoid if the Alltrax is seeing low voltage. I had that happen to me a couple years ago with similar symptoms.

Thanks. I'll swap it out and see if symptoms improve. It's a tough one because it happens randomly, but I guess only one way to find out.

[Volt_Ampere]

Also, you can hook up your laptop to the Alltrax and log the runs. If it fails, you will see in the log why it failed. It helped me solve my solenoid problem.

[superfan86]

Originally Posted by Volt_Ampere

Also, you can hook up your laptop to the Alltrax and log the runs. If it fails, you will see in the log why it failed. It helped me solve my solenoid problem.

I ran logs but haven't parsed them yet. Will do if after bedtime with the 4 year old.

[superfan86]

Update: new solenoid and the issue still persists.

Still trying to figure out why the cart would be at 14 mph even with the Alltrax. That HAS to be a symptom here. Controller is reporting 100% throttle, so MCOR not to blame.

[superfan86]

Update: The friend says that this jerky behavior started after I installed the Alltrax. This is not my first install, I've done 4 other DS carts, so I'm confident I have it wired correctly.

Installed the new solenoid and the jerky behavior happened immediately. Gave up and came back an hour later and the cart drove fine for 10 minutes around the neighborhood, albeit still capped out around 13 mph in both Forward and Reverse, even though I have reverse speed set to 50%. Alltrax monitoring was screaming about low voltage the entire time too


I pulled the logs off the cart last night when it was doing the jerk/no move. Looking at them all I see is a low battery condition, but the pack voltage was reading 48-50v by my Volt meter at that same time, so some kind of symptom there.

[jasonojordan]

Is your meter reading this under load or resting?
IF your meter is reading that at the same time under the same conditions as the alltrax I would double check all connections for corrosion between the pack and the alltrax.

Have you reached out to alltrax about the issue?

Originally Posted by superfan86

Update: The friend says that this jerky behavior started after I installed the Alltrax. This is not my first install, I've done 4 other DS carts, so I'm confident I have it wired correctly.

Installed the new solenoid and the jerky behavior happened immediately. Gave up and came back an hour later and the cart drove fine for 10 minutes around the neighborhood, albeit still capped out around 13 mph in both Forward and Reverse, even though I have reverse speed set to 50%. Alltrax monitoring was screaming about low voltage the entire time too


I pulled the logs off the cart last night when it was doing the jerk/no move. Looking at them all I see is a low battery condition, but the pack voltage was reading 48-50v by my Volt meter at that same time, so some kind of symptom there.

[superfan86]

Originally Posted by jasonojordan

Is your meter reading this under load or resting?
IF your meter is reading that at the same time under the same conditions as the alltrax I would double check all connections for corrosion between the pack and the alltrax.

Have you reached out to alltrax about the issue?

I have verified all the connections are clean and tight.

I put the cart on the charger, and despite the claim "it was fully charged" The charger kicked on and hummed for over 8 hours. After 5 I took it for a spin and the issue didn't present. I'm wondering if the lack of maintenance on these 18 month old batteries is causing them to present good voltage but dive under load. I just refused to consider it given they are so new and good quality Crowns.

I also changed the motor setting from 8 pole to 4 pole and the speed increased from 15 to the expected 20+. Odd given the motor is the AMD and I was still using Scottie's map, but at this point I'll just take that win.

I'm hoping that this is just one of those weird things where the issue was so obvious that I refused to recognize it, but I'll keep this thread updated if I end up calling Alltrax.

[jasonojordan]

Glad you have made some progress.

Originally Posted by superfan86

I have verified all the connections are clean and tight.

I put the cart on the charger, and despite the claim "it was fully charged" The charger kicked on and hummed for over 8 hours. After 5 I took it for a spin and the issue didn't present. I'm wondering if the lack of maintenance on these 18 month old batteries is causing them to present good voltage but dive under load. I just refused to consider it given they are so new and good quality Crowns.

I also changed the motor setting from 8 pole to 4 pole and the speed increased from 15 to the expected 20+. Odd given the motor is the AMD and I was still using Scottie's map, but at this point I'll just take that win.

I'm hoping that this is just one of those weird things where the issue was so obvious that I refused to recognize it, but I'll keep this thread updated if I end up calling Alltrax.