Mopar brake controller issue, help needed.

[JPAloha]

Long post alert:
As we tow with both of our two doors I decided to add the Mopar trailer brake controller into the 2018 as well as our 2019.
The one in the 2019 has been in and working for almost two years.
Since the 2018 did not have the factory tow package I added the towing wiring, hitch and brake controller wiring kits.
The trailer lights all work as they should, the plug for the brake controller has good voltage, ground and power in from the brake input wire.
I’ve checked for voltage at the hitch plug and have constant voltage on the blue wire whether the brakes are applied or not.
The issue I’m having is that the controller itself doesn’t seem to do anything. It doesn’t illuminate on start up whether the trailer is plugged in or not.
Pressing the brake override doesn’t activate the trailer brakes as it does when I do that on the 2019.
I would be inclined to conclude that the brake controller is defective but I have tried two of them.
Im hoping someone else has had this issue and resolved it. I’m at a loss on what to check next.

Sponsored

 

[Yellow Cake Kid]

I don't have a good answer, but I recall that the OEM trailer parts for add-ons were listed as not applicable to the earliest models, which does not mean it will not work but does suggest there are some gotchas.

One detail I recall is that the brake controller signal interfered with the antilock braking system signal.

Jeep updated the vehicle software to solve the issue, but another solution utilizes a blocking diode wired in the signal path.

Maybe some of these ideas will lead you to more pertinent and useful information.

Good luck.

 

[Jeep Wick]

Long post alert:
As we tow with both of our two doors I decided to add the Mopar trailer brake controller into the 2018 as well as our 2019.
The one in the 2019 has been in and working for almost two years.
Since the 2018 did not have the factory tow package I added the towing wiring, hitch and brake controller wiring kits.
The trailer lights all work as they should, the plug for the brake controller has good voltage, ground and power in from the brake input wire.
I’ve checked for voltage at the hitch plug and have constant voltage on the blue wire whether the brakes are applied or not.
The issue I’m having is that the controller itself doesn’t seem to do anything. It doesn’t illuminate on start up whether the trailer is plugged in or not.
Pressing the brake override doesn’t activate the trailer brakes as it does when I do that on the 2019.
I would be inclined to conclude that the brake controller is defective but I have tried two of them.
Im hoping someone else has had this issue and resolved it. I’m at a loss on what to check next.

It sounds like your brake controller is not wired correctly. Your constant power on the blue wire is a tell. Perhaps the fix is swapping the wires in the 4 pin plug you put together. Double check where these are and which one goes to battery.

 

[JPAloha]

It sounds like your brake controller is not wired correctly. Your constant power on the blue wire is a tell. Perhaps the fix is swapping the wires in the 4 pin plug you put together. Double check where these are and which one goes to battery.

I have them in the correct order albeit with different colors.
I realize the constant on isn’t sounding correct either though.

Tan and Red goes to the battery via a 30amp fuse.
white is the connection to the B15 wire (green/white), brake input.
Black is the ground wire.
Blue is the brake output wire.

 

[Jeep Wick]

I wonder if your brake input wire is faulty. There should be no voltage on that or the blue wire until you press the brake. If that's working correctly I would say you have a bad controller.

 

[JPAloha]

I wonder if your brake input wire is faulty. There should be no voltage on that or the blue wire until you press the brake. If that's working correctly I would say you have a bad controller.

The brake input wire is providing voltage only when the brake is pressed.
While unlikely, it isn’t impossible to have received two defective units.
Ive reached out to the supplier, a dealer in BC, to ask for help.
They plan to test the returned unit and go from there. They’re saying they will ask one of the electrical expert technicians for their opinion on it also.
Meanwhile, I need it to be functional by the weekend if possible.
I appreciate your replies on the thread btw.

 

[Jeep Wick]

The brake input wire is providing voltage only when the brake is pressed.
While unlikely, it isn’t impossible to have received two defective units.
Ive reached out to the supplier, a dealer in BC, to ask for help.
They plan to test the returned unit and go from there. They’re saying they will ask one of the electrical expert technicians for their opinion on it also.
Meanwhile, I need it to be functional by the weekend if possible.
I appreciate your replies on the thread btw.

I know it's a hassle but have you tried swapping them between your other Jeep?

 

[JPAloha]

I know it's a hassle but have you tried swapping them between your other Jeep?

I did try the first unit in my wife’s 4xE but didn’t see it illuminate on start up as the one in my 2019 does. Admittedly didn’t try it with the trailer connected. 4xE and the 2019 both have factory tow package.

 

[JPAloha]

I don't have a good answer, but I recall that the OEM trailer parts for add-ons were listed as not applicable to the earliest models, which does not mean it will not work but does suggest there are some gotchas.

One detail I recall is that the brake controller signal interfered with the antilock braking system signal.

Jeep updated the vehicle software to solve the issue, but another solution utilizes a blocking diode wired in the signal path.

Maybe some of these ideas will lead you to more pertinent and useful information.

Good luck.

On my 2019 I did change the connector from the factory plug to the controller for one with a diode in it. This eliminated the warning lights.
I was actually hoping to see the warning lights occur on the 2018 as a sign it was working properly. This one is acting as though it isn’t turning on at all.

 

[Jeep Wick]

I did try the first unit in my wife’s 4xE but didn’t see it illuminate on start up as the one in my 2019 does. Admittedly didn’t try it with the trailer connected. 4xE and the 2019 both have factory tow package.

I installed 2 Redarc controllers on Jeeps without the tow package, so it is doable. Unlikely you got 2 bad units, but anything is possible.

 

[Yellow Cake Kid]

Hi,
I have been wondering, were you able to get the gremlins worked out?

 

[JPAloha]

Hi,
I have been wondering, were you able to get the gremlins worked out?

Sorry, just saw this.

Yes, eventually.
It was a combination of things:
The first two units they sent were shorting internally causing the constant power on the blue wire.
The third unit they sent I decided to test in my 2019 as it had a controller that worked perfectly. It worked there as it should. Moving it to the 2018 it worked (I could hear a click when pressing the emergency button) and then it didn’t. I realized that the multiple install and removals and the angle the wires coming to the plug had to bend resulted in at least two wires becoming fractured (worked fine when I straightened them out, did not work when they were in the bent position they needed to be in).
I cut the wires, put new pins on them and reassembled the plug. All is now well.

 

[Yellow Cake Kid]

Great news.

Thanks for the update.

Sponsored