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Trailer brakes faint

Creek Jenkins

Well-known member
If you have a steerable endoscope it is easy to go in through the 3/8” hole in the backing plate and have a look at the seal. That is how I found one of mine was leaking. Much easier than pulling the drums.
 

dogbalou

Member
I think the general opinion is to not use the ez lube zerk to pack the cavity full of grease, as you will squeeze it past the seal. The port is at a bearing, and if used, should just require a couple of pumps while spinning the wheel to lube the bearing. My port has never been used because I did not want what I discovered to happen.
 

nav39

New member
Here is my issue. Reaching out to anyone that my have a solution. The dealer is worthless.
2025 f250 diesel.
My first truck was a 2020 f250 gas and the trailer brakes worked grate pulling my new goose neck trailer. They would lock up any time I manually applied the brake controller.
Now with my new 2025 f250 diesel the trailer brake work but only slightly. I have had two new trailer hooked up to the truck and the results are the same. Very little braking and will not lock up when the trailers are empty.
So fare I have check the braking voltage out of the 7 pin and this is what I got.
No trailer hooked up. Gain at 10 13 volts when manually applying trailer brakes.
Trailer plunged in. Gain at 10. Manually applying trailer brakes 11 volts.
Trailer plunged in. Gain at 10. pressing an brake pedal 4 volts.
Today I will cut the wire on the trailer going to all 4 brakes and check amperage output with my volt meter.
I suspect one of three things.
Factory wiring.
Brake control module.
Brake controller.
I believe that 2023 to 2025 F250 / F350 will be the same set up.
Any one have this issue.
Thanks
 

BryanValRox

Elite Member
So just a couple of thoughts, be careful with your test, some truck controllers need to see speed in order to output via pedal.

Have you reviewed this video ?


What type of brake are on the trailers you are testing, magnetic, hydraulic, or disc?

Have you thought about applying 12 volts and a ground to the 7 pin brake wire on the trailer to ensure you get activation.

Have you checked your trailer for proper brake adjustment and or grease containment linings?
 

Dan54

Well-known member
Have you pulled an RV with this truck before? I ask, as our prior F-250 did not come with the required fuse to send power to the 7-pin plug....even though it had integrated brake contoller.

If you do have that part working, I'd have someone increase the level from say 2 up to 10 and I would be using a volt meter to test the voltage increase coming off the brake connection on 7-pin

View attachment 2980
I might have the same issue. 2024 paradigm 340rl/2026 f350. Doesn’t seem to have much trailer braking. Also on my boat trailer, 2015 Malibu Txi 21ft inboard ski boat/Boatmate single axle trailer w/surge brakes & reverse brake override, the brakes lock up when backing up. Boatmate thinks it’s not getting the electric signal to release the brakes when the truck is placed in reverse. Ford dealer has no clue what I’m talking about. Im not sure if that’s the same pin as the brakes. To compicate matters more my boat mechanic ruined the wiring pigtail coming off the boat by getting it caught on something while it was in for winterizing. They replaced it with an aftermarket part & changed with wires around on the truck trying to get it to work. Now I’m looking at getting it back to factory specs so I hope the wire colors on the diagram are accurate to my truck.
Also to test the #2 pin does the ignition need to be on & engine running? Brakes applied?
Thanks
 

Oregon_Camper

Forum Admin
Staff member
I might have the same issue. 2024 paradigm 340rl/2026 f350. Doesn’t seem to have much trailer braking. Also on my boat trailer, 2015 Malibu Txi 21ft inboard ski boat/Boatmate single axle trailer w/surge brakes & reverse brake override, the brakes lock up when backing up. Boatmate thinks it’s not getting the electric signal to release the brakes when the truck is placed in reverse. Ford dealer has no clue what I’m talking about. Im not sure if that’s the same pin as the brakes. To compicate matters more my boat mechanic ruined the wiring pigtail coming off the boat by getting it caught on something while it was in for winterizing. They replaced it with an aftermarket part & changed with wires around on the truck trying to get it to work. Now I’m looking at getting it back to factory specs so I hope the wire colors on the diagram are accurate to my truck.
Also to test the #2 pin does the ignition need to be on & engine running? Brakes applied?
Thanks
Have you set up different trailer profiles in your truck? Does our Alliance have disc or drum brakes? Check the trailer profile in your truck to match the type of brakes you have. I had to change our F-450 to "Electric over Hydraulic" when we picked up our 340RL that has disc brakes.
 

Dan54

Well-known member
Have you set up different trailer profiles in your truck? Does our Alliance have disc or drum brakes? Check the trailer profile in your truck to match the type of brakes you have. I had to change our F-450 to "Electric over Hydraulic" when we picked up our 340RL that has disc brakes.
I’m not sure what type of brakes, probably drum. Bought the trailer new off the lot. I assume disc brakes were an option. I would take a look but that’s a 4 hour round trip. What are the other brake profile options? I don’t remember what I selected But yes I set up profiles for my trailers.
Have you pulled an RV with this truck before? I ask, as our prior F-250 did not come with the required fuse to send power to the 7-pin plug....even though it had integrated brake contoller.

If you do have that part working, I'd have someone increase the level from say 2 up to 10 and I would be using a volt meter to test the voltage increase coming off the brake connection on 7-pin

View attachment 2980
I have the trailer profiles set up correctly I believe so I’m moving to the fuses. Where is the fuse box for your missing fuse located, the engine compartment or cab?
 

Oregon_Camper

Forum Admin
Staff member
I’m not sure what type of brakes, probably drum. Bought the trailer new off the lot. I assume disc brakes were an option. I would take a look but that’s a 4 hour round trip. What are the other brake profile options? I don’t remember what I selected But yes I set up profiles for my trailers.
Ford trailer brake settings are adjusted via the dashboard's Productivity Screen under "Towing," allowing you to select brake type (Electric or Electric-over-Hydraulic) and effort (Low, Medium, High—Low is default). The Gain setting ss adjusted using buttons on the controller to match trailer load
 

Dan54

Well-known member
Not sure where to go from here. All fuses that are related to towing are present. Don’t have a fuse puller for these fuses so I didn’t check them.
Tested the 7 pin with voltmeter & couldn’t detect any voltage. Had the leads on the 1 & 2 pins, ignition on, level at 8.5, compressed the manual tabs & depressed brake pedal - nothing. Even though the level isn’t 10 I should be getting voltage. Also in the profile braking was set to Medium. Any suggestions? Thanks
 

Oregon_Camper

Forum Admin
Staff member
. To compicate matters more my boat mechanic ruined the wiring pigtail coming off the boat by getting it caught on something while it was in for winterizing. They replaced it with an aftermarket part & changed with wires around on the truck trying to get it to work. Now I’m looking at getting it back to factory specs so I hope the wire colors on the diagram are accurate to my truck.

When connected, do your trailer brake lights work when brakes applied?

I just went back and to read your issue again and Jesus...that is NOT cool. Who is their right mind changes the trucks wiring to match the F' up they did to the boat trailer wiring? I think you need to have RV dealer pay Ford, to have them change the wiring back to factory. Once this is done...then check your RV's brakes again.
 

BryanValRox

Elite Member
Not sure where to go from here. All fuses that are related to towing are present. Don’t have a fuse puller for these fuses so I didn’t check them.
Tested the 7 pin with voltmeter & couldn’t detect any voltage. Had the leads on the 1 & 2 pins, ignition on, level at 8.5, compressed the manual tabs & depressed brake pedal - nothing. Even though the level isn’t 10 I should be getting voltage. Also in the profile braking was set to Medium. Any suggestions? Thanks
A suggestion, don’t run down a rabbit hole until you know the basics are good. Start by making sure the fuses are good!
If someone was messing with wires, it is possiable they blew a fuse.

Also, I believe that both Ford and Ram recently announced recalls related to the trailer brake controllers.
I believe it requires a software update to prevent the operation from dropping out.

Could your model be affected?
 

7426TRISS

Well-known member
RAM 2026 did have a recall, the letter is coming out in March. Brake Controller Software Update.
I just got mine in December 2025 and towed only 20 miles, no problems. But I was driving without the RV and on the instrument display, one time showed trailer connection, then disappeared. We will see an advise
 

M and E

Prominent Member
I’m not sure what type of brakes, probably drum. Bought the trailer new off the lot. I assume disc brakes were an option. I would take a look but that’s a 4 hour round trip. What are the other brake profile options? I don’t remember what I selected But yes I set up profiles for my trailers.

You can email Alliance with the last six of your vin and they'll tell you what is on your rig.

Also, I believe that both Ford and Ram recently announced recalls related to the trailer brake controllers.
 

Dan54

Well-known member
When connected, do your trailer brake lights work when brakes applied?

I just went back and to read your issue again and Jesus...that is NOT cool. Who is their right mind changes the trucks wiring to match the F' up they did to the boat trailer wiring? I think you need to have RV dealer pay Ford, to have them change the wiring back to factory. Once this is done...then check your RV's brakes again.
My apologies, I didn’t proof read well enough before I hit send. Should have read: “Changed the wiring on my boat trailer…”
 

Dan54

Well-known member
Does anyone have a description of the new (to me) fuses on these trucks? Name, size or whatever? Also the removal tool?
 

Fishfnatic

Well-known member
My fuse was under hood. If you look in owners manual for fuse locations it should show you which one is for trailer brakes. Of course I did not have brake lights at all so maybe not same.
 
Last edited:

dogbalou

Member
Here is my issue. Reaching out to anyone that my have a solution. The dealer is worthless.
2025 f250 diesel.
My first truck was a 2020 f250 gas and the trailer brakes worked grate pulling my new goose neck trailer. They would lock up any time I manually applied the brake controller.
Now with my new 2025 f250 diesel the trailer brake work but only slightly. I have had two new trailer hooked up to the truck and the results are the same. Very little braking and will not lock up when the trailers are empty.
So fare I have check the braking voltage out of the 7 pin and this is what I got.
No trailer hooked up. Gain at 10 13 volts when manually applying trailer brakes.
Trailer plunged in. Gain at 10. Manually applying trailer brakes 11 volts.
Trailer plunged in. Gain at 10. pressing an brake pedal 4 volts.
Today I will cut the wire on the trailer going to all 4 brakes and check amperage output with my volt meter.
I suspect one of three things.
Factory wiring.
Brake control module.
Brake controller.
I believe that 2023 to 2025 F250 / F350 will be the same set up.
Any one have this issue.
Thanks
I would pull at least one of your front drums off and look at the shoes. I had bad seals on mine after just a few hundred miles. The brake shoes were covered in grease and I had almost no brakes. Just replace the backing plate if that is the problem, the pads will never be the same if you try and clean them. I run my gain at 7.5 now and feel safe.
 
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