No Reverse After Curtis 500mp Controller Upgrade

[Tater65]

I have a 2001 Club Car DS with Plum Quick Bandit and I just upgraded the controller from stock Curtis 225 amp to Curtis 1205M 500 amp. I rebuilt this cart a few years ago and have upgraded the F/N/R, solenoid to heavy duty and all cables are upgraded to 4 gauge. Forward works fine but no reverse. Hooked everything back up as it was but I did have to make a modification to the J3 terminal since my old controller had a smaller blade terminal. When I put it in reverse and hit the pedal I hear the solenoid engage and see the volts go down when I accelerate but no movement. The wire colors and terminals are J1=red, J2=green, J3=yellow. Any ideas what the issue could be? Thanks in advance for the help.

[Fairtax4me]

Possibly a wrong connection at the FNR switch.
If your FnR switch has two terminals on the bottom, they may need to be bridged together via cable or copper jumper bar to provide voltage to the motor for reverse operation.

It could also be an incorrect connection at one of the microswitches. One of the microswitches on the FNR has to pass the throttle signal to the controller. When reverse is selected the throttle signal goes through a resistor that cuts the signal down for half speed reverse. If the resistor is damaged, or if the wiring there has been modified or hooked up incorrectly the controller may get no throttle signal at all when reverse is selected.

[Tater65]

What’s odd is reverse worked fine with my old controller and I hooked everything back up in the same order. Any idea why the J3 terminal on the controller would be a different size than my 225 amp controller? That’s the only thing I modified with a bigger plug on the J3 terminal. Runs great in forward just no reverse now.

[Fairtax4me]

The controller has no affect on forward or reverse.
Motor direction is changed by reversing polarity of the field current and that is done by the FnR switch on a series cart.

Either the controller is not getting a throttle signal, or the motor is not getting power.

Check your crimp connection on that new terminal, make sure it’s tight.

Otherwise you need to start checking for proper voltage at the FnR switch and microswitches.

Can you post pictures of the FnR switch and the connections there?
How about at the controller?
Post pics of the battery compartment as well so we can see the battery cable routing and cable connections at the FnR switch.

[Tater65]

Here’s a few photos of my FNR wiring. The folks from where I purchased the controller are telling me to remove the green and white wires from the limit switch and splice together and remove the black wire and tape it off. Supposedly that will give me reverse in the same speed as forward.

Technical Support at Curtis told me this today “ The F/R switch is a high current switch, you are manually making the contact for the motor field and not energizing it via a Forward/Reverse contactor.
I guess the Limit Switch 3 was the switch that became active during reverse operation, and limiting the speed to ~50%.
But that is not needed with the new controller now, hence Advantage’s direction for splicing the green & white wires together.
To get the reverse limiting speed on your new controller you need to add in a reverse signal at the J5 terminal, or get the parameter “Rev Input / Main Driver” programmed = 0
You could actually repurpose the limit switch 3 that when reverse is active, it carries the voltage from the Keyswitch (or anywhere that is close by you can tap off of) to the J5 terminal”.

I’m still not clear what to do but splicing the two wires together sounds like the easiest fix.