Trouble Shooting Tekonsha Primus IQ Item # TK90160 On 2018 Jeep Wrangler JL With Factory Tow Package

Question:

I have this controller installed on a 2018 Jeep Wrangler JL factory tow package and wiring harness the controller is plugged in using the Tekonsha adapter pigtail. It was working quite well. Then, when I applied the Jeep brakes, the trailer brakes engaged quite aggressively. Not enough to lock up, but not smoothly as before. I had made no changes to the controller, and the digital readouts were as previously set. Then, it quit working altogether. Now, when the trailer a small Forest River popup is plugged into the Jeep, I get a .c on the controller. When I depress the Jeep brake pedal, I get a 00 readout. Checking the controller preset, I get a 7, which is where Ive had it all along. I dont find any info on the .c readout. Can you tell me what Ive got here? Thanks.

asked by: Mike

Helpful Expert Reply:

That is a great question and brake controllers can be nerve racking to figure out at first. The ( .c ) on the Tekonsha Primus IQ Item # TK90160 installed in your 2018 Jeep Wrangler means your trailer is connected but the boost feature is off. If it shows ( .c. ) then it means trailer connected with boost feature on. The 00 means you have the power control knob set to 0. You may also see this if you are sitting still applying the brakes. If you have the trailer connected and you hit the manual override while sitting still, the number that shows on the screen means your trailer brakes are receiving 7 volts. Keep in mind the vehicle and trailer need to be moving in order to test the adjust the braking pressure to the trailer. I recommend at least 15 miles per hour in a safe, flat, unobstructed location.

What you can also try is unplugging the brake controller for about 35 seconds then plug it back in. This will basically reset the controller. I typically recommend setting the control knob at about 5 and slightly adjusting from there for the trailer weight. Once you have the setting where you want, play with the boost mode. It will have 3 settings. The ( .c ) means no boost as mentioned before, then b.1, b.2, b.3. You only want to use the higher boost setting when you trailer load is heavier. If the trailer load is lighter and the boost level is set high the braking will be too aggressive.

I have provided a link with the instructions for setting up and trouble shooting situations with that brake controller.

expert reply by: Shane H