Hale

I am trying to install a trailer brake controller and everything is fine except that the pin that should be supplying power when the brake is applied is dead.
Any thoughts other than running a wire from the back of the vehicle as to how I can get 12V when the pedal is depressed?

fabbrisd1

Have you installed a Modulite into the system - you can't just go wire-to-wire you know, right ?

Hale

No. I have been following the MB bulletins and previous postings on controller instillation and no one mentioned anything other than "plugging the quick connect into the MB plug that is part of the code 550 tow package".
Apparently on my ML the particular pin in question is dead.
I have no idea what a modulite is or have I seen the word used in any of the posts. If it is the circuit breaker for the power to the brakes, that has been installed,

DUTCH

Which brake controller are you trying to connect? Are you using the instruction sheet discussed in this thread?

https://mbworld.org/forums/new-m-cla...ol-module.html

Do you have the connector from the trailer plugged in to the socket at the hitch? Without an electrical load from the trailer being plugged in, there may be no voltage to the brakes.

Are you measuring the voltage when making a stop with the trailer connected? Keep in mind that the accelerometer in the brake controller acts on the slow down inertia of the tow vehicle to send a variable voltage to the trailer brakes. This variable voltage is dependent on how hard you are braking the rig.

Hale

Sorry, I did not state the problem clearly.
The issue is at the X58/28 connector.
The grey or black/red wire -- the brake light circuit does not energize when the brake pedal is depressed therefore the controller doesn't get an activation signal.
The brake lights on the vehicle work and if push comes to shove I can splice into the circuit at the back of the vehicle and run a wire back up to the dash but I am trying to avoid that.

DUTCH

You did not answer my question. Do you have a trailer connected when you test the circuit?. I get no power to the brake light wire unless there's a trailer connected. There is an ECU in there that controls everything, and it needs the load of a connected trailer to function.

I'm trying to help you; but if you won't answer my troubleshooting questions, I'm done.

Hale

Sorry, no trailer connected.
I didn't see anywhere in the other posts that the trailer had to be connected to the vehicle.
I will try to arrange that with the instillation people.
Would it be possible to use a dummy load to simulate the trailer? I am a bit tense with the idea of dragging a 24' car hauler through a busy city without brakes.

MLee

Go witha Tekonsha wireless system. All you need is a jump wire at the trailer plug on the car powering the aux and brake pins.......job done.

Lee

DUTCH

You could try a dummy, but I don't know if it will work or not. My Tekonsha P3 has a diagnostic mode that tells you exactly what voltage and current is where.

DUTCH

The Tekonsha wireless does not work with some trailer brake systems. It will not work with the US made Carlisle electric over hydraulic brake system on my Australian Kimberley Karavan.

Check with Tekonsha and your trailer brake system manufacturer to be sure.

Hale

The system I have purchased is the Tekonsha P3. What do you think of finishing the installation, take the vehicle home where I have some elbow room hook up the trailer, and see what the unit does?
Is there a manual override on the P3 or a way of adjusting it so that the activation of the trailer brakes is obvious?
I am asking all of this because the hitch shop is in a location where it is difficult to turn around the M-B and having a trailer would be virtually impossible.
Thanks

DUTCH

Yes, there is an override on the P3. It's the swing lever on the bottom of the unit. It will apply the full braking voltage that you have set using the arrow keys on the left side of the screen.

There's also a diagnostic menu. Check your Owners Flyer or download the attachment below. It will give you several different voltage and current readouts.

Also, Tekonsha's Customer Support is based in Michigan and is superb!

Hale

Bit of a delay getting back -- we are also in the process of moving.
Thanks for all the help -- hooked up a dummy load plus a rack of lights and everything works.
As stated in this thread the controller has to "see" a trailer or no brake light signal. Just wish this was stated somewhere in the instructions.
Again many thanks. Now if I could just get the vehicle to stop telling me I am going too fast.

DUTCH

You're most welcome, although some folks don't like me to post here.