"Trailer Disconnected" despite lights working

[mrtroy32]

I have a 2017 Ford F-250 and a 2017 Dutchman Kodiak 37' TT. For the last year, when I plug the 7 pin connector into the truck, the truck detects the trailer, correctly identifies it as the Kodiak, and everything works (lights, electric brake controller, battery charging).

As of last week, when I plug in the 7 pin connector, the truck does not detect anything or even recognize that a trailer is connected. If I manually select that the Kodiak is connected, it throws up the "Trailer Disconnected" message as soon as I exercise the brake controller (either through the pedal or the manual brake slider). However, the trailer lights and signals all work even when the truck says there's no trailer connected.

I took my truck to a friend's TT and plugged it in and the truck immediately detects the trailer correctly, then I brought her truck over to my TT and her truck is not able to detect the trailer either, so it's clearly a problem with the Kodiak.

Any ideas on what is wrong? I checked all the fuses, though none are labeled to have anything to do with that, and all are fine.

TIA!

 

[ATCguy]

If you're not even getting trailer lights when you plug it in now, then you've probably got a problem with the RV pigtail... either the plug itself, the wiring in the pigtail, or the wiring in the junction box where the pigtail connects with the rig. Something's obviously become disconnected... either via a broken wire, or just a wire connector that's unplugged somewhere along that line.

 

[mrtroy32]

That's just it, I am getting lights when I plug it in, it's just not detected and the electric brakes aren't working. The pin out diagram from Dutchman shows which pin is responsible for the electric brakes, i suppose just that one wire could be compromised somewhere, I might have to check into that.

 

[ATCguy]

Yeah, we just had a discussion about brakes a couple weeks ago. Check out the posts in this thread:

http://www.dutchmenowners.org/forums/f20/intermittent-trailer-brake-issue-7728.html

 

[sundancer 87]

That's just it, I am getting lights when I plug it in, it's just not detected and the electric brakes aren't working. The pin out diagram from Dutchman shows which pin is responsible for the electric brakes, i suppose just that one wire could be compromised somewhere, I might have to check into that.

Good luck with finding the problem. My Chevy nags me about 'service trailer brake system' without a trailer connected. The problems range from dirty 7 pin connections to brake controllers to brake light switches to defective plugs and even front wheel speed sensor.
Trailer lights will work but the brake is a different circuit. It's usually a heavy blue wire if that helps.
Forgot to mention the 30 or 40 amp fuse or relay under the hood.

 

[mrtroy32]

Yeah, we just had a discussion about brakes a couple weeks ago. Check out the posts in this thread:

http://www.dutchmenowners.org/forums/f20/intermittent-trailer-brake-issue-7728.html

I saw that one but I'll go ahead and read the whole thing, thx!

I actually used to get a "Trailer Wiring Fault" message, and I found that one of the wires to the electric brakes was rubbing the tire and had worn off the insulation, causing a short. I taped it up and the problem went away, that was actually the first thing I checked with this problem too.

 

[jeffwelsh]

I had that same problem. One of the connections is loose. On mine the installers stripped the insulation and the crimp connector was not hitting the wires. The truck's brake controller needs to detect the resistance from the brakes.
-Jeff

 

[mrtroy32]

I had that same problem. One of the connections is loose. On mine the installers stripped the insulation and the crimp connector was not hitting the wires. The truck's brake controller needs to detect the resistance from the brakes.
-Jeff

can i use a voltmeter to test that pin at the plug before I go tearing through the underbelly?

 

[mrtroy32]

I found the lippert electric brakes manual, and there's a fairly comprehensive troubleshooting section with great instructions for an electrical novice like myself: https://lci-support-doc.s3.amazonaws.com/manuals/axles-and-suspension/ccd_0001730.pdf

 

[Franktafl]

Mine did the same thing only I have four locations to look for the mystery fuse or breaker.. found it under the hood about four feet from the regular furs block. Check your connections first. Did you plug your friends trailer into your truck?

 

[mrtroy32]

Did you plug your friends trailer into your truck?

Yes, and my truck detected her trailer just fine, that's why I'm 99% sure it's a trailer wiring problem.

 

[sundancer 87]

I had that same problem. One of the connections is loose. On mine the installers stripped the insulation and the crimp connector was not hitting the wires. The truck's brake controller needs to detect the resistance from the brakes.
-Jeff

Interesting concept with the controller needing to sense resistance. Can you offer the explanation of that? I know we have 7 wires that each have their own function but I don't know of a return wire to provide the resistance to the controller.
How is the resistance need satisfied when there isn't any connection to RV/truck? Another question, does the controller adjust itself according to axle configuration?

 

[persistent]

Test with TT emergency breakaway switch

Trailer does not work on two tow vehicles.
A different TT works on both vehicles.

The problem is clearly with the trailer wiring from the 7 pin connector to the break magnets and then to ground.

Hook up the TT. Pull the TT emergency switch pin. If the breaks tighten up, it is in the circuit between the 7 pin and the connection box where the emergency circuit ties in. Replace the emergency switch pin immediately after testing. (It can cause melted breaks if left on for a long time)

 

[Thom]

Check the blue wire......

https://www.etrailer.com/question-143231.html

:wink

 

[jeffwelsh]

Checking Brake Connections

All of my connections are by the wheels on each axle. There is a wire that runs outside the underbelly and your first connections should be there and be on each side of the axle. Wires running to the other side run through the axle and have connections there. Mine actually had an extra connector at each wheel that I eliminated.
-Jeff

 

[mrtroy32]

So to follow up, I found the problem...

The last guy I paid to repack my wheel bearings failed to put the pin in the shaft that holds the magnet in place inside the brake assembly. I know he didn't put it in at all because it wasn't down inside the casing when I took it off, where it would be if it had popped off afterward. So on my last trip, which was particularly bumpy, the wiring had worked itself around in there due to the loose magnet and eventually got snagged and cut.

 

[acdii]

Sounds like you got it. For those who have the Ford Smart Trailer in their trucks, it works by sensing connectivity and resistance. The lighting is tied to both the 4 pin, and the 7 pin, so it works for any type trailer, but the 7 pin must be able to see that there are brakes in the circuit before it will activate the module.



So unless it detects at least 6 Ohms (3-4 Ohms per magnet)resistance, it will think that no trailer is connected to the 7 Pin, but to the 4 pin instead and not provide power to the brakes. This is only with the trucks with the Integrated brake controller though. So with the OP's magnet wiring chewed up, it will either be a direct short, or an open circuit, either way the system faults and will not provide braking.



On the lighting, it also detects resistance as well and can tell if one bulb is burned out by lack of resistance on that lead. The lighting is different because lights are usually 1.5 ohms per bulb for 12v lights. If there are LED lights installed, this can cause issues with the truck reporting a light out condition since LED bulbs usually have very low resistance, measured in tenths of an ohm. For these applications, a housing for LED lights will usually have a resistor built into the circuit to prevent module issues with some vehicles. If you plan to install LED bulbs into your trailer lights, make sure you get bulbs designed to be a direct replacement for the type of bulb being replaced as they have resistors in them.

 

[OldOneTwo]

If you put your 4 way flashers on do you have your side marker lights blink too? If so you have a ground problem. Either loose or corroded open.

 

[seventhfire]

Might check the operation of the breakaway switch. Link below
https://www.etrailer.com/faq-tb-11-06-test-trailer-breakaway-system.aspx

 

[drchaffe]

Sounds like it is the pigtail connected to the trailer. When reversing it's easy to get that cable kinked or pinched and it may have just broken or shorted out one or two wires inside the rubber outer layer. Inspect it carefully for this type of damage.