Thomas C2 multiplex brake controller

[Vermonster]

Hello all. I have been unable to find any information that will guide me through setting up a brake controller on my C2.

I have a 2012 Thomas C2 with hydraulic brakes. So far none of my local dealers know how to setup the trailer wiring in the multiplex system. I want to town a double axle BigTex car hauler and my Jeep.

Etrailer and Fleet Pride said they had nothing that would work for me.

If anyone can guide me I would greatly appreciate it. If I can’t figure this out I will have to go another route and get another skoolie I suppose.

Thanks in advance.


2012 Thomas C2 Freightliner
Cummins

 

[s2mikon]

I can't see why this won't work. https://www.etrailer.com/Trailer-Brake-Controller/Tekonsha/90885.html

 

[Vermonster]

I was told nothing would work with the multiplex. I spoke with two different people at Etrailer.

 

[ewo1]

Not sure if this would work for you but the manufacturer states "Compatible with tow vehicles that have multiplex wiring systems".

Not sure if this means your bus is the tow vehicle?


TEKONSHA 902502 PRODIGY® RF PROPORTIONAL TRAILER BRAKE CONTROLLER 1-3 AXLES)

https://www.hannarv.com/P/24432/Tekonsha90250ProdigyRFBrakeControl

 

[Vermonster]

Thank you for the reply.

This brake controller setup is for a vehicle that already has the wiring installed. I have a multiplex system that has no brake wiring. I need to tie into the wiring system and run all the wires to the rear of the bus.
I might be able to find the wiring schematics somewhere, but I was told that even if I tie into the bus wiring directly, the multiplex computer may sense a different level of resistance and shutdown. The only tech that has been willing to help me just stated that he doesn’t know if it will shutdown or not.
I don’t want to fry my wiring or, of course, have the possibility of losing my brakes while towing. Maybe someone with multiplex experience can advice if this will happen and/or how to prevent it.

 

[ewo1]

Thank you for the reply.

This brake controller setup is for a vehicle that already has the wiring installed. I have a multiplex system that has no brake wiring. I need to tie into the wiring system and run all the wires to the rear of the bus.
I might be able to find the wiring schematics somewhere, but I was told that even if I tie into the bus wiring directly, the multiplex computer may sense a different level of resistance and shutdown. The only tech that has been willing to help me just stated that he doesn’t know if it will shutdown or not.
I don’t want to fry my wiring or, of course, have the possibility of losing my brakes while towing. Maybe someone with multiplex experience can advice if this will happen and/or how to prevent it.

Yes, be cautios!

I would give them a call though and get more details on how the wiring works.

Another thing that I myself would look at, is your multiplex signals driving relays that sends control (+12v) voltages to the lights and if so, can you tap into the relay output contact themselves to get the control voltages for your brake controller setup or just installation of a 7 way plug instead?

In other words, not directly tapping into the mutiplex side of the signal, but into the relay output side itself.
I wonder if that would work?

 

[ewo1]

Hello all. I have been unable to find any information that will guide me through setting up a brake controller on my C2.

I have a 2012 Thomas C2 with hydraulic brakes.

.......

If anyone can guide me I would greatly appreciate it. If I can’t figure this out I will have to go another route and get another skoolie I suppose.

Thanks in advance.


2012 Thomas C2 Freightliner
Cummins

I just found this site that has numerous docs/ppt on the Thomas c2.
It has service manual info and quite a few circuit diagrams.

Maybe you can find some useful info there!

https://myersequip.com/resources/product-downloads/

 

[s2mikon]

You could install a second brake light switch and a second set of brake lamps and you would be fine. If you were able to convert your bus then you have the skills already. Most of these universal controllers use an inertia sensor to apply the trailer brakes proportional to your tow vehicle slowing down. The also light up the brake lights when applied. You could just go around your present system and be safe.

 

[Vermonster]

Thank you both for the feedback.

I am a little over my head when it comes to in-depth schematic reading and this type of system. I have hooked up a brake controller or two before, and I had a proportional controller on my previous skoolie, but I am not confident about this.

I will get in there there and look at the relays themselves and see if it’s possible to tap into them. The tech mentioned a relay box or something in the driver side fender, I will see what that looks like.

 

[Vermonster]

I think I might try this setup.

 

[RoosterSocks]

I've researched this pretty extensively for my own C2, I just started on the trailer wiring. Without swapping the Chassis module for one that has trailer outputs, the best and most complete option seems to be a DirecLink J1939 Brake Controller. https://tusonrvbrakes.com/products/direclink-dl-100

 

[1dmpo]

Surge brakes

I think you've gotten some good information so far and can probably make electric brakes work but my first thought was maybe go to a trailer with hydraulic surge brakes. No worries at all about screwing up your multiplex wiring then.

 

[Jolly Roger bus 223]

i have trailers with juice brakes and electric brakes and i prefer the electric brakes because you can set there intensity.
gain/loss/sensitivity.