2008 Ruff & Tuff Hunter EV - Half speed in forward and no torque in reverse

Hello all. I’m assisting a neighbor with his 2008 R&T Hunter and we need a little help. The specific issue is the cart will run at half speed going forward and it has no torque in reverse. The issue is consistent and doesn’t change over time. The cart has been to a repair shop and the following items have been swapped, tested, and/or verified:

  • All batteries changed with known good set and issue persists
  • Speed solenoid changed and issue persists
  • Motor has been pulled, brushes checked and tested for short - no short in motor
  • Checked all shafts, bearings, brakes, etc. Everything moves freely and nothing is creating drag
  • Verified all wire connections clean and tight

The controller is a CTL7500D 48 Volt 650A and this cart does not have a 1/2 speed switch in the glove compartment.

Trying to find information (wiring diagrams and testing specifications) has proven to be a challenge and any advice would be greatly appreciated. Thank you!

I believe the 2008 has a series motor. Controllers are not that expensive. I put one in my brothers 2008.
That’s about all that’s left.
Are you sure the throttle is pushing/pulling the pot box rod all the way in? If it’s like the one I remember, a cable from pedal to box way upfront. Watch the pin move into the box at wot. Can you push it further by hand? Only short by 1/4" will limit to 1/2 throttle.

Thank you for your response, Inwo! My neighbor verified the throttle is pushing the rod all the way in at WOT. He did make a minor alignment adjustment and is currently charging the batteries to test for any change. With ignition switch on (while charging batteries), we did notice a red LED on the controller blinking (two blinks, then one blink… long pause then same repeating pattern) possibly code 21?

Is there a green led too?
It should blink after the red blinks once and again after the red blinks twice.

Good to know, Thanks! We did not have a direct line of sight on the red LED but rather saw the reflection. Will try again tomorrow to get better visual on the LED’s. Any advice on where we can find a trouble code legend for the CTL 7500?

Only Google.
If it’s a Curtis clone 21 is low voltage.

That makes sense. The batteries are low and currently charging. Here’s a pic of the CTL7500D controller. Do you recall if your brothers was a Curtis and do you know if they are inter changeable?

I had to rewire it for a Chinese Curtis. Doubt if you will find a plug in replacement.
Seems as though I ordered it with a throttle to make it easy.

Find the throttle wire. One of them will go 0-5v when wot.
If it does throttle is ok.
I don’t know which pin is 1/2 speed. It may have gotten mis conected.

Perfect. I just found a wiring diagram for a 2008 R&T Hunter which has the connector pin-outs so should be easy to test throttle. Also, just checked and only has red LED. Thanks again for your input. We are eliminating potential culprits.

Inwo, the cart is working now! My neighbor noticed the throttle plunger was binding in the ITS at WOT and made a corrective adjustment yesterday. After that adjustment and charging the batteries, the cart is now operating as expected. Thank you for providing your input and guiding us in that direction. He wanted me to send his sincere thanks for helping solve an issue that has plagued this cart quite some time.

Super, it only takes a tiny bit to be 1/2 throttle.
Fine me a 2009 R&T . I want to hot rod one for myself. Just finished one up for a buddy. Fast and powerful with big ac motor.
Only the 2009 has a 19 spline motor. I think!

Hi. Would really like a wiring diagram for the 2008 hunter.
How can i get one ?