Autowbrake Electric Brake Controller

I had The Nest upgrade mine, too.
Along with CTEK for the solar roof.

 

I installed my autowbrake controller on the back of the storage compartment. I feel the is a better option for me as removing the battery controller is annoying enough without another big clunky thing with wires attached to it.

First I removed the right hand brake light, it is held in place by a rubber ring and easy to remove. I verified that the area behind the compartment back panel had clearance and drilled a 1/2" hole for the cable. I then threaded the cable through the hole and mounted the controller to the panel. The screws that came with the controller are too short to get a good purchase in wood so I found some longer ones. Connecting the wiring up is made much easier by having the tail light out, the brake/turn signal wires are easily found back there.

I also removed the battery and hooked up the controller power wires in there. The ground wire is hooked to one of the ground studs. The power wire should go to the power feed from the 7-pin; I connected it to the input+ terminal on my DC-to-DC converter. I am not sure if connecting the power to the trailer battery will be OK as it will be powered up all the time. It might impose a small drain on the battery all the time, and it will use power from the battery to activate the brakes.

I tested the functions and did the calibration steps in my driveway, I haven't taken it on a test drive yet.

 

The brake controller does have a good drain on the battery. I just remove the fuse on the bottom of the brake controller when in storage. My parasite drain is down to 1 % with the brake controller disabled.

 

Cary mentioned that when we were talking. I hope that Autowbrake takes it seriously -- if this is being marketed to "boat" and "RV" towable market --- many of those sit for long periods of time, I can see a lot of dead batteries out there because of it, especially if they are using the small "lawn mower" batteries which is not at all uncommon...

 

Good tip, thanks!

 

Cary was talking about this, its part of the official delivery training now. I still think it is a major design flaw on the part of the autowbrake controller company. It should "sleep" if not activated for some period of time...

 

The problem is avoided by connecting the autowbrake power to the 7-pin power feed. Of course this requires the battery isolator or DC to DC converter.

 

I believe that Autowbrake is taking this seriously.

When I was troubleshooting parasitic drain in the trailer, I managed to create (and subsequently detect) a faint buzzing from the Autowbrake controller when its supply voltage dropped below some voltage. I took this to be some sort of cut-out/cut-in indecisiveness and they were very interested in my report -- to be fair, I believe that my power drain was occurring somewhere else in the trailer, and **not** originating with the Autobrake.

I brainstormed a few ideas for new features (such as a the crazy idea of an on/off switch that is accessible while driving -- my TV is an EV, so I dream of diverting the braking power into the EV regen system rather than the friction brakes). I have misgivings about the sensibility of this idea but at least they didn't completely dismiss it.

Has anyone tried to measure the quiescent drain accurately? Are there transients?

 

Some cars, including my Highlander, cut the 12v feed at the hitch when the key is turned off. Per my testing.

On the other hand, and I’m not completely sure if I’m remembering this correctly, several or multiple or all states require electrically activated trailer brakes to engage if a trailer disconnects from the tow vehicle. Which is the function of the breakaway switch. Would that still function if the Autowbrake controller was powered from the hitch?

 

Neat idea. "Diverting the brake energy to battery charging".

You'd need new hubs and regen "brakes" in the form of electrical motors that harvest the induced load.

There's got to be a semi-trailer manufacturer working on this idea?

 

The Camp Inn breakaway switch powers the brakes from the trailer's battery. The Autowbrake can independently operate the brakes from the tow power if it is connected there, both functions will work. In my installation I tested the breakaway function after installing the controller and it works.

 

Over the holidays I had some time to try an experiment measuring parasitic drain from the Autobrake controller. It turns out that the Autowbrake controller represents a significant power drain if left connected to the battery (and with the main switch disconnected). The graphs below show the charging current after 1 week idle time with either the Autowbrake connected, or disconnected (by temporarily removing its fuse). In both cases the master switch is disconnected.

The lesson is to keep the trailer connected to shore power whenever possible -- if it has to remain disconnected, then disconnecting the Autobrake via the fuse can reduces the parasitic power loss considerably.