Troubleshooting Difficulty Calibrating The Redarc Tow-Pro Liberty

Published 11/08/2023

Products Featured in This Question

Redarc Tow-Pro Liberty Brake Controller - Dash Knob - Up to 2 Axles - Proportional

(2504)

$190.00

Redarc Encapsulated Power Diode for Tow-Pro Brake Controllers

(15)

$60.00

Plug-and-Play Wiring Harness for Redarc Tow-Pro Classic, Elite, or Liberty Trailer Brake Controllers

(308)

$35.00

Question:

Calibration issue with Tow-Pro Liberty in 2021 Toyota 4Runner. I recently installed the Tow-Pro Liberty into my 2021 Toyota 4Runner using the RED49FR TPH-021 harness. After install, the break controller will not calibrate. I have seen a few things online about why this may be happening but wanted your opinion. One reason I have heard is that there is a diode built into the RED49FR harness AND there is a diode that is in the Toyota 4Runner trailer break plug. This is causing the voltage to be too low and is why calibration wont happen. I have also seen some people say they need to add a diode to the harness to make it work. So I am a little confused as to what the problem is and how to fix it. Any recommendations would be helpful.

asked by: Matt

Expert Reply:

We have never encountered a case of a 4Runner needing a diode in order to use the Redarc Tow-Pro Liberty # RED24FR. If you suspect voltage is low you could always go in and test with a volt meter.

The Redarc Encapsulated Power Diode # RED34FR is generally only needed on vehicles with certain advanced safety systems like the Adaptive Cruise Control, Assisted Emergency Braking and Autonomous Emergency Braking. Since you are using the plug-and-play pigtail # RED49FR you should not need any additional components.

We do suggest that you make sure that the controller is mounted securely in a fixed location. The controller can be installed in any orientation, but it cannot move, as this can throw off calibration.

Also, sometimes the calibration process can take time. Sometimes you will need to speed up and slow down repeatedly up to 20 or 30 times in order for the unit to fully calibrate. Also, if no trailer is connected, the unit will calibrate without any indication from the LED. We suggest disconnecting the controller from power, then plugging it back in and re attempting calibration. Even better if you can do this with the trailer connected.

expert reply by: Jesse M