Troubleshooting Curt Spectrum Output and Sensitivity Adjustment

Updated 06/23/2024 | Published 07/20/2023

Question:

Setting up the Curt Spectrum I have run into a contradiction. The instructions say to set gain with vehicle parked foot off brake. I found another that says To adjust your brake controller output, press and hold the vehicle brake pedal. Set the output to the starting value specified in the instructions. This is confusing because I am having some issues getting a good smooth stop. When I come to a stop, it is jumpy, best way to describe it. Others have said to use the manual control rolling the vehicle and apply the manual control until it stops and record the number and apply that to the gain output. Any suggestions will be greatly appreciated, Thank you

asked by: Gary

Expert Reply:

It sounds like the sensitivity needs to be adjusted on your Curt Spectrum # C51170 since it is too aggressive leading to the jumpy stop. To adjust the output and sensitivity you want to follow the instructions. This means you only make adjustments while stopped, with the transmission in park or neutral, parking brake applied, foot off the brake pedal, and no manual control actuation.

Adjust the sensitivity by pressing the rotary knob until the brake control is in the sensitivity control mode. Blue-red LEDs will appear on the LED display. Rotate the knob clockwise or counter-clockwise as needed to set the sensitivity control.

Find a dry and level paved or concrete surface. drive forward at approximately 25 mph and press the brake pedal. The vehicle and trailer should make a smooth stop. If the stop seems slow and more aggressive braking is desired, adjust the sensitivity level by rotating the LED display knob clockwise. If the stop seems too aggressive, adjust the sensitivity level by rotating the knob counter-clockwise. Make several stops at various speeds and adjust the sensitivity until stops are smooth and firm. Slight adjustment to the output control may also be desirable.

I have attached the full instructions for adjustment below for your reference.

expert reply by: Robin H

Curt Spectrum Adjustment.
(click to enlarge)

Michael B.

6/23/2024

Any chance you could specifically address the OP’s conflicting instructions, i.e, why the brake pedal mustn’t be pressed or how such an instruction could have come to exist? Are there situations where pressing the brake pedal during adjustments work for one narrow aspect of control leading one to a false sense of correct functionality?

Robin H.

6/23/2024

@MichaelB I haven't seen any conflicting instructions. The picture above is from the current set of instructions for the brake controller which is what you should follow. If there is an older set of instructions out there that say something different I'm sure Curt made the change after finding this works better. All it is saying is to make adjustments while parked with the foot off the brake pedal. Then you drive forward and apply the brakes via the brake pedal to test them out. If you need further adjustment park, adjust, then test again.