EDITED as of 27/01/2020
So it’s been a while since I have updated the site as I have been building a custom off road camper as you can read all about here.
Now that I am installing electronic brakes on the camper, I needed to install myself a brake control unit. Now, there are plenty on the market and I’m not the person to give you any recommendations on which one is better. I will tell you I went with the Hayman Reese CompactIQ® Brake Controller.
What I will tell you is how I installed it which may save you some time should you decide to install one yourself. Please note that all electrical work should be completed by someone who knows what they are doing and I take no responsibility for any damage you may cause by attempting the installation. Now that that’s out of the way, lets get down to business.
This particular brake controller unit only required four wires to be installed.
Power (Positive and negative – not Ground), brake input and brake output to trailer plug.
Lets start with Installation location. I installed the control unit under the start button, there is a nice space there and also that’s where I wanted to install my brake controller adjustment (I have run out of blanks so I used the space beside).
I made a small right angle bracket and mounted the brake controller in the position detailed in the fitting instructions.
I then ran two wires, through the firewall located directly behind the same location into the engine bay and over to the battery. I placed a 20amp fuse on the positive wire and and attached the wires to their respective terminals.
Two wires down, two to go.
Now the instruction tells you to tap the brake pedal switch which for me was not as easy as it sounds (there are some wiring harness that have piggy back plugs however mine did not). I decided to connect mine to the tail light wire which activates when you press the brake pedal.
This needs to be tapped on the other side of the tow ECU which should be located in the jack access panel as per Graham’s comment below.
I belled out the brake wire coming from the tow ECU and tapped that wire. I then ran the tap all the way back to my brake controller.
I’m about to save you about an hours worth of work right here. Now you could run a wire from the control unit all the way to the brake light, or you could just use the brake light wire I traced all the way from the tail light to the passenger kick panel which makes this install so much easier. Remove the passenger protection strip and then the kick panel. Once removed you need to locate the (Blue and orange) wire and (Blue) wire.
In this picture (above) this is the blue and orange wire. This is the brake light wire.
You should always test this for yourself in case this has changed with the later models. Simply use a multi-meter or test light which should activate when the brake pedal is pressed.
In the picture below, this is the blue wire. This is the brake wire that goes to the trailer plug (assuming you already have a tow kit installed otherwise why would you be installing a brake control unit.)
I then tapped into these two wires and ran them across to the driver side behind the dash and connected them up to the brake control unit.
I am not a fan of quick taps or scotch locks so I soldered directly to the wires.
With everything connected, it was time to test. I hooked a multi-meter to the trailer plug and measured the voltage when I manually activated the brake controller by pressing the button. All good, I had voltage coming through and everything appears to be working.
I did notice as soon as I pushed the brake controller button I got an alert on the dash saying the FCM was unavailable????? It took me about 30 min to work out what was going on. The vehicle computer was disconnecting the FCM as the break line was having power drawn from it without the brake pedal being pressed so the computer was thinking there was an error. As soon as I pressed the brake pedal and then manually activated the trailer brakes the error was not thrown up.
This issue does not occur now that that the brake light is tapped after the tow harness ECU.
I am not sure when you would manually activate the trailer brakes without the brake pedal pressed because this is the whole reason to install the brake controller so it is automatic, never the less I’m sure there is a reason for it, (I just used it for testing everything works.
Here is the explanation for the manual override brake from Graham.
“manual over ride is very commonly used when towing vans. It is useful on long descents for an additional ‘touch’ and very useful to control trailer sway by ‘stretching’ the rig from the rear…instantly stops sway. You need manual over ride.” Thanks Graham!
If I have missed anything or you would like more info, please let me know. Happy 4WDing!