Bench Test Trailer Tow Module

[Shrapnel Steve]

Mopar part 68092732AE

Truck:
2014 Ram 2500
5.7 Hemi
SLT

Issue:

In the spring on a slushy day I noticed the trailers breaks weren't working and as I was away from the shop I checked all the lights and proceeded carefully home to see if another wire had broken. Unfortunately for me the drive way has a slight downward inclination and the slush and ice allowed the trailer to push me sideways. A replaced tail light later I stopped towing with the Ram and waited for the nicer weather to climb under it. After checking all the wiring carefully I ended up in the cab looking at the part mentioned above, it had been installed by the local dealer a month after I got the truck in 2014 but this little piece was just tucked in behind the dash trim, which seemed odd but hey its been there 6+ years and I was none the wiser. Again checking for wire continuity I noticed a red wire wrapped around a partially stripped brown wire going in to this same part. I followed the wire (red) up behind the dash and found it tied into the radio harness of the new aftermarket radio I had installed last fall before winter lock down.

Now can I be sure the red wire has anything to do with this issue? No.
What is the Brown wire? Unsure.
Had the trailer breaks been working since the radio was installed? Not sure as the staff drive this truck more then I do.
Can I bench test this module to confirm its working or dead?

I went to the dealer a few weeks ago about it and the tech assured me it had to be a broken wire in the trailer harness cause the module wasn't throwing a code. This seems dubious now.

the images below show the red coming from the radio harness and the brown wire that it was wrapped around. you can see the green wire that runs from there to the trailer connector and that wire shows no breaks. It would appear they were powering the radio via this brown/red combo, but the radio still works and the trailers breaks don't

 

[AFMoulton]

Who installed the radio? I’d start there.


2018 Ram 2500 6.4L 4x4
Amsoil SS 0W-40

 

[WY-Dave]

First thing I would warn everyone about the shoddy job the radio installer did.
Here are the connectors that are listed a Module-Trailer Towing at http://connectors.dcctools.com/home.htm





and the 7 wire connector


if you take a voltmeter to test B & C and push the brakes, you should see a voltage.
This will atleast test the whole system up to the trailer.

 

[SheapnelSteve]

It was a local shop who did the install. I’ll be contacting them Monday but they aren’t essential and maybe closed for the lock down again.

anyway to test this on the bench with it out? The truck isn’t registering a trailer attached so I don’t get any break control while all the lights work

 

[SheapnelSteve]

WY-Dave any chance you know what fuse the tan/red might be? I’ve check the trailer break fuse 30amp and it’s ok but it started to rain so I had to pack up before exploring further

 

[WY-Dave]

Sorry haven't answered earlier. I don't know where it goes to or comes from. I been looking for an online source for wiring diagrams, well free ones haha, but can't find snot. If you have a volt meter you can go between 1 & 3 on C1 and see if there is any juice. Don't forget to go through all scenarios (key out/key acc/key run/brake on etc). If you dont have a voltmeter, you can get couple pieces of wire and a 12v lightbulb and test it that way. I had to do that using a dome light bulb when I was out camping once to check a circuit.

 

[GTyankee]

I suggest that first you look at the trailer plug at the back bumper, you will be checking for corrosion & crud.
It may look alright, but just to be sure you will want to spray both the truck & trailer plugs with Electric Contact Cleaner, like CRC or LPS

2) when you pickup the contact cleaner, get one of these too



It is a trailer wiring tester, it may cost $10 - $15

Doing the electrical spray is common maintenance & insures that the contacts are not shorting out

The tester will tell you which if any wires are hooked up to the trailer brake module

Watch this video & listen too
It is the complete installation of a 2014 brake controller, it also shows where the wiring is suppose to go

 

[Shrapnel Steve]

Thank you GTyankee

so I did multimeter and test light that I still have power. I checked continuity and the wire shows good front to back.
The dealership installed the controller years ago and apart from the mounting brackets they optioned out of it’s been working fine. The computer still shows all the trailer towing options but just says not connected. I have a tester like you suggested and it won’t trip the brakes as my understanding is the computer is sending the resistance in the magnet and the tester just shows lights working not the break.
I picked up a replacement module but it’s not showing anything different. Of course it was used and could be dead but I find it unlikely. Any other thoughts lol. May have to go Reece and abandon the factory gear

 

[Shrapnel Steve]

Thank you GTyankee

so I did multimeter and test light that I still have power. I checked continuity and the wire shows good front to back.
The dealership installed the controller years ago and apart from the mounting brackets they optioned out of it’s been working fine. The computer still shows all the trailer towing options but just says not connected. I have a tester like you suggested and it won’t trip the brakes as my understanding is the computer is sending the resistance in the magnet and the tester just shows lights working not the break.
I picked up a replacement module but it’s not showing anything different. Of course it was used and could be dead but I find it unlikely. Any other thoughts lol. May have to go Reece and abandon the factory gear

I have also bypassed the plug altogether and went new wire into the trailer break and the computer still doesn’t see it

 

[Shrapnel Steve]

Multimeter shows nothing at the trailer even with new wiring