Jumpy/all or nothing

[Jlile5]

36V DCS EZGO cart

-Put Alltrax XCT48400 in a few years ago.
Upgraded to 4ga wires
- All new batteries last month

Every time I turn the key on, I have to flip the tow/maintenance switch off, then back on. The Solenoid will then click and then I can go and everything is normal. But FWD reverse lever has to be in FWD or the solenoid won’t click. The controller is blinking code for low voltage but voltage is good. I even hooked laptop up and set the voltage minimum real low. Also, reverse has always been funny.. you have to hold it to the floor and there’s about a 5-6second delay and then you better be ready to launch backwards..
I have changed the pedal micro switch, and the FWD/Reverse micro switch.. nothing changed except making the cart extremely jumpy in both directions.

I have updated the controller and added the 4ga wiring but the solenoid is still the stock one.. could this have anything to do with it??

Appreciate any help/advice!

[bronsonj]

What is your throttle rate? If you set your throttle rate too high it can cause jumpiness. Also if you switch to lithium you'll have to reduce your throttle rate because the lighter weight will make it feel too jumpy.

Your throttle rate may have no relation to your current issue, but it's one possibility.

I doubt your solenoid would cause jumpiness.

[JohnnieB]

I have a sneaking suspicion the contacts in your stock solenoid look about like those in the attached images, or worse.

Stock solenoid was only rated at 80A and was barely marginal with a stock controller and should have been upgraded when the controller was upgraded.

Install a SW180 or other 200A solenoid, or larger, with 400A controller.

Replacing the solenoid will likely fix the jumpy issues, but if it doesn't we can troubleshoot more after the solenoid is replaced.

[Jlile5]

Thanks for the part #! I’ll get it coming my way. I knew at the time of changing the controller that I needed to upgrade the solenoid but it was one of them “I’ll just throw the controller in it so I can use it and change the solenoid later” type deals lol

Appreciate the advice, I’ll report back after it’s installed and let y’all know!

[Jlile5]

Originally Posted by bronsonj

What is your throttle rate? If you set your throttle rate too high it can cause jumpiness. Also if you switch to lithium you'll have to reduce your throttle rate because the lighter weight will make it feel too jumpy.

Your throttle rate may have no relation to your current issue, but it's one possibility.

I doubt your solenoid would cause jumpiness.

Sorry, didn’t see your reply earlier!
It’s been a couple weeks since I had this laptop hooked up and was messing with the throttle rate. I don’t have the answer to your question, but I do know that when I messed with the throttle rate it didn’t matter, it was still the same. It’s almost all or nothing in FWD and it absolutely is all or nothing in reverse.


Any body happen to know what diode I need for the Curtis SW180? Or is the diode off the stock solenoid ok to use?

[JohnnieB]

Diode recommendations are in boxes on right side off attached schematic of an XCT in a DCS cart.