My truck did not have a tow package when sitting in the lot, so the dealer installed one. The brakes have never worked on any trailer I have pulled. I always assumed it was the trailer wiring. But I have found the other day that my trailer wiring is fine and that there is no voltage at the plug on my truck...lighting works fine, but no brakes. Now to answer the simplest and most obvious reason for no brakes...yes I have the controller and yes it functions properly according to a test light. I can diagnose electrical issues very well...But I don't see how an electrical issue would be possible ever since the truck was new and the package was installed. My question here is...Does anyone know of something that the technician may have missed as to why the brakes never functioned? There is the little blue plug that the controller hooks to up under the dash and there is the 7 pin trailer plug in the back...is there maybe some connection in between these two that didn't get hooked up properly? Does anyone have an electrical schematic for the trailer wiring on this truck? It's a 2006 1500 if that makes a difference.

 

When you put your foot on the brake pedal, does your brake controller indicate any brake funtion being recognized? You mentioned a test light, is this it's own, or a "probe type" of test light?
(does any sort of light or status indicator show a change?) Is the brake controller gain setting turned up high enough to apply the trailer brakes so you'd know if they came on?

If above is so, then check the plug at the back of the truck - activate your brake controller manually and confirm that there is voltage to ground at the brake terminal (it has it's own terminal, different that the left and right turn signals.) it may not be a full 12-14 volts, depending on what your brake controller is sending.

If no voltage, then start confirming fuse integrity.

Also, have you confirmed correct operation of the trailer brake system with a different tow vehicle

 

All they probably did at the dealer was plug in the new 7 pole plug to the 4 pole already on your truck thus giving you just trailer lights. You have to run a wire for the brakes to work. Follow these steps to install the wire you need for the trailer brakes to work.

Factory Installed 4-Pole

If you drive a newer Dodge Ram Truck (~1995 - Present) and your vehicle already has the factory installed 4-Way flat trailer connector then only a few extra parts are needed. Although, not all late model trucks with a 4-pole has the brake controller plug. Make sure to double check if you have a 2005-2007 model truck to see if the truck as the correct port.

Parts Needed:

1. The Brake Controller
2. The Universal, Tekonsha, or Valley Brake Control Adapter
   • Sometimes this will be provided by dealer.
3. 7-Way or 6-Way 4-Pole Adapter
4. Wire - number of feet depends on truck bed size and hot lead

Step 1:

Start by plugging in the brake control adapter into the OEM harness located under the steering wheel, just to the right of the emergency brake pedal. Then find a place to mount the brake controller. It should be in a position that is easily accessible (See Above). Connect the wires. If the port is not available, see the start from scratch.

Step 2:

Usually located under the driver's side of the vehicle, right behind the front wheel well is a wire connector. As you can see in the picture there are more wires on the hood side (right side) of the connector than the hitch side. Using a circuit tester you can locate the wire that supplies power to the trailer brakes. Usually it is the blue one. Using a scotch lock, run a wire lead from the blue wire to the back of the vehicle. Enough wire will be needed to make it from the front wheel well to the end of the truck bed. The wire lead will connect to the blue wire on the 7-Way or 6-Way trailer adapter. After mounting the new trailer adapter and plugging it into the original 4-pole connector, installation is complete.

Note: If a hot lead is needed, it would need to be connected to the battery via a circuit breaker. That wire would then connect to the black wire on the trailer connector adapter.

 

I am BEYOND pissed off at my dealer. After owning the truck for 5 years, I finally had the ambition, time, and weather (simultaneously) to go troubleshoot my truck wiring for trailer brakes. Come to find out, there was a harness that went from the 7 pin plug in back all the way up to the front and I saw it was near the brake booster...so I got up and looked under the hood and saw that they just coiled it up and zip tied it to vacuum line of booster. This end of the harness had a red wire and wht/red with a fuse between them, the other end of red wire went to battery POS. Then (and here's the anger) the blue wire coiled up with them, no connector or anything, never stripped, nothing...the effing thing was never tied into the fuse block...5 years of taking risk of towing with no trailer brakes and the dealer didn't do their frickin $500 job. I was so pissed I was going to just hook it up myself, since the dealer obviously isn't capable of doing it right, and come to find out it is a circuit board behind all of the harness connectors...So I couldn't solder it right behind the fuse terminal...I guess I will have to find a connector that can be put into the harness...or should I go to the dealer and b!t(h them out until they fix it??

 

What a PITA. I hate those stealerships. If you want something done right....

 

Yeah man we learn the hard way. I put brake controllers in all the time at work and i think we only charge like 175 for hard wiring both the brake controller and 7 way plug and thats with labor. And you know half the time its the stealerships sending them to us. We charge them that price and they jack the price up to whatever they want. Its a shame.

 

Yeah, the dealer did mine for sure, didn't ship it out, cuz I was sitting there the whole time...the $500 included the hitch and wiring and install, no controller, had to go buy that seperate...I shoulda just done it myself, but when they said the truck doesn't have the tow package, but it can be installed, I thought it was the FULL package, HD alternator, HD cooling, etc for the $500 come to find out, I think I was wrong and got what I mentioned above...

 

So if you install them...do you know where I can find a pin connector that slides into the harness connector, so I can hook it up so it looks original??

 

Well you really wont be able to make it look original. If you already have everything, you will need to do 2 things, 1)route the blue wire, that was tied up, through the firewall and hook it to the blue wire on the brake controller. 2)Route a (30amp)fused hot wire from the battery to the black wire on the brake controller. Taken that your brake controller has 4 wires (red,black,white and blue)The red wire on your brake controller should be hooked up to your brake light signal, Black is your constant 12v hot, white is ground and the blue is your output brake wire that goes to your 7 pin connector. I hope i didnt confuse you. Let me know if have any questions.

 

Didn't confuse me at all, but all that is already done...the harness is there up under the dash where all I needed was the pigtail from the controller to that plug. That harness is fine, everything is where it needs to go. The blue wire goes to the fuse block to fuse number 12 which is labeled electric brakes. But the other side of that fuse is empty...and in the wiring the dealer did, the blue wire is empty in the front, but goes all the way to the back 7way plug...so this blue wire needs to be tapped into the fuse block and then it'll all end up being correctly connected. This is where I am worried about looking original...I don't want to do a hack-job hooking to the fuse block....the rest I couldn't care less about appearence. I'm looking for a correct pin that goes into the empty slot of the wiring harness connector for the electric brakes fuse (12)...and I found from the schematic that is is location C10 on the harness...so I can splice it onto the end of the wire and have it in the proper way through the harness to the fuse.

Thanks for helping