trailer brake warning message
Yep your truck should come with it. 
sorry I had too.
I am guessing you are asking why it might be on. this might help.
Ford F350 Brake Warning Light: Why is it on? | Drivetrain Resource (700r4transmissionhq.com)
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I contacted Kiara at Ford at 1:48 PM on 07/07/2020 about CAS-37519831; she wanted me to go to a dealer. So went to Sanderson Ford and talked to the service manager about the warning message that fills the entire dash “WIRING FAULT ON TRAILER”. When this message appears no other information appears on the dash, which requires you to hit the OK button while braking to clear a message as you are driving with no apparent cause or meaning. I think having such a large warning sign while braking is a hazard. The dealer has no way to troubleshoot why this warning is coming on. He has no technical detail on how much brake current is too much at any given speed or how much input to the microprocessor is receiving from the other computers on the truck. Since there is no interest from Ford in fixing the hazard it creates. I need to report this driving hazard to NHTSA about removing the Hazard warning label while using the brakes to slow or stop the F-350 truck.
The manual under Information Display Warning Messages has this statement: “the trailer brakes may be drawing too much current” what does that mean ? The dealer does know what that number is. I never have that warning light appear when pulling a double axle trailer with 4 brakes. I appears often a lot when pulling a triple axle trailer with 6 brakes. I think the Ford trailer brake system cannot handle the current draws when all 6 brakes are engaged. But with no spec supplied to the dealer and no way to test what that trip point is, the warning is a hazard during a stopping event each and every time it happens.
The microprocessor controls all of these items yet the dealership cannot check or verify any of these operations.
- The trailer brake controller is equipped with a feature that reduces output at vehicle speeds below 11 mph (18 km/h) so trailer and vehicle braking is not jerky or harsh. This feature is only active when applying the brakes using your vehicle’s brake pedal, not the controller.
- The controller interacts with the brake control system and powertrain control system of your vehicle to provide the best performance on different road conditions.
- Your vehicle’s brake system and the trailer brake system work independently of each other. Changing the gain setting on the controller does not affect the operation of your vehicle’s brakes.
What I need Ford to do is help the dealer run checks or simulations to stop the need for the Hazard Notification with no solution to be displayed on the dash that block all normal displays that are shown on the dash.
Trailer Fault Indicator on Dash
Can you change the parameters on the Ford brake controller ?
Can the dealer change the upper current limit on the brake controller when engaging 6 brakes on a triple axle trailer ?
I looked in the Manual as to why does the trailer fault display on the dash
The dealer tech does not have all the parameters on the brake control
That’s what I’m requesting what are the parameters that the brake controller sees before the display is shown on the dash
I think the random display is caused by the trailer brakes exceeding the current draw limit built into the brake controller.
This display warning only occurs with this triple axel trailer toy hauler, no other trailer causes the warming. But the other trailers do not have 6 electric brakes connected to the F-350. When the brakes are applied too hard all 6 brakes draw too much current versus a dual axle trailer with only 4 brakes needing current.
Sanderson has done the simple test that dealers can do, they find no problems with the very basic test. A trailer repair place said there is no problem with the trailer brakes. And the warning hazard does not occur on an ongoing regular basis only when the brakes are applied too hard.
I push the OK button everything is fine until I apply the truck brakes too hard, which causes all 6 brakes on the trailer to engage, this again exceeds the upper limit that the brake controller thinks is excessive and displays the warning on the dash. Most trailers only have two axles or 4 brakes, not 6. This exceeds the controller trip point for a higher than normal current draw.
The solution is to program the control to a higher trip point due to 6 trailer brakes drawing higher Amps during a normal braking operation.
In the Ford manual on page 296/666 it states this:
TRAILER BRAKE MODULE FAULT Displays in response to faults sensed by the trailer brake controller, accompanied by a single tone. If this message appears, contact an authorized dealer as soon as possible for diagnosis and repair. The controller may still function, but with degraded performance. WIRING FAULT ON TRAILER Displays when there is a short circuit on the electric brake output wire.
On page 297/666 it states this:
If this message displays, with no trailer connected, the problem is with your vehicle wiring or trailer brake controller. Contact an authorized dealer. If the message only displays with a trailer connected, the problem is with the trailer wiring. Consult your trailer dealer for assistance. This can be a short to ground (such as a chaffed wire), short to voltage (such as a pulled pin on trailer emergency breakaway battery) or the trailer brakes may be drawing too much current. Points to Remember Note: Do not attempt removal of the trailer brake controller without consulting the Workshop Manual. Damage to the unit may result.
• Adjust the gain setting before using the trailer brake controller.
• Adjust gain setting, using the procedure above, whenever road, weather, trailer, or vehicle loading conditions change from when the gain was initially set.
• Only use the manual control lever for proper adjustment of the gain during trailer setup. Misuse, such as application during trailer sway, could cause instability of the trailer or tow vehicle.
• Avoid towing in adverse weather conditions. The trailer brake controller does not provide anti-lock control of the trailer wheels. Trailer wheels can lock up on slippery surfaces, resulting in reduced stability of trailer and tow vehicle.
• The trailer brake controller is equipped with a feature that reduces output at vehicle speeds below 11 mph (18 km/h) so trailer and vehicle braking is not jerky or harsh. This feature is only active when applying the brakes using your vehicle’s brake pedal, not the controller.
• The controller interacts with the brake control system and powertrain control system of your vehicle to provide the best performance on different road conditions.
Thus controller has a microprocessor that handles all of these inputs from different systems on the F-350 truck.
Have you tried a different 3 axel 6 brake trailer to see if it still occurs?
That’s like renting a Lotus for a couple of hours in Erie Pa
A three axle trailer to rent with a 7 pin connector is hard to find
U Haul only rents 2 axle trailer with a flat four pin connector
I have rented 2 axle trailers of the same weight with a seven pin connector with no problems
I picked up 3 axle trailer and drove it home a 3 to 4 hour drive. The first time I had to slow down from 55 to 35 the trailer warning turned only 20 minutes into the drive home. When the warming light came on I was worried I was going to drive without trailer lights all the way home in the dark on I 10. Luckily after I ran around the trailer in the setting sun all the trailer and brake lights worked. I have been looking for a solution to the warning coming on when towing the triple axle trailer since February 2021. Dual and single axle trailers using the 7 pin connector never cause the warning light on the dash to appear.
Where do you rent a 3 axle trailer that is a bumper pull with a 7-pin connector that weighs 11,000 lbs ?
The bigger question is how do you get Ford to do something about the problem or work with the dealer to check into the complaint ?
The Ford OEM trailer brake system is run by a microprocessor, that will require the code to be modified by Ford.
Ford has not shared the parameters of the trailer brake system operational parameters with their dealer network.
That’s like the 721 Firestone tire once they found out it was the tire’s fault the dealer couldn’t fix it.
sorry YOU ARE GOING THROUGH THIS. i really cant help because I do not have enough experience with trailers. the only other info I can give is back around 2008 there was a big problem with fords having the same warning. a lot were fixed because the problem was that water was getting in the 7-pin connector. when they took them apart there was a lot of water found inside. just a thought. wish you the best with this problem.
The reason I mentioned that is because that is the only trailer you are having a problem with. if that trailer plug has water or corrosion in it, it could cause the warning. the other trailer plugs have no water or corrosion, so no warning. maybe it is something as simple as that. like I said it is just a thought.
Keep calling Ford corporate and keep complaining. Try another dealer… your’s might not be up to snuff on their technical training.
Which will not not fix the problem you are having. If the 3 axle trailer draws too much current, that is a hardware issue. Ford Legal likely will not let them turn off the displayed message.
So says ONE dealer. They may be lying to you or just ignorant.
No it isn’t. Ford did not MAKE the Firestone 721s, nor did they warranty them. Firestone made the tires and warranted them.
I’ll ask you a question…have you measured the current draw on your 3 axle trailer while operating the brakes either connected to the truck or stationary? Voltage and current as well as the quality of the grounds. There are 2 parts to this problem … the truck and your trailer. You need to know your trailer’s wire is up to spec (most are crap based on my personal experience and the number I see running down the road with non-functioning lights)
You say Ford doesn’t share the parameters… but if they did, how would you know if your trailer is in or out of spec if you don’t know the current draw?
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Seeing this only happens with the 1 , 3 axle trailer, has anyone checked that the brakes on the trailer are ok ?
It may be your trailer that has the problem, not the Ford.
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Trailer brakes a Car Talk topic again? Oh no!! … lol …
Problem with Fords OEM Brake Crontroller as Supplied as Part of the New Vehicle
I had a trailer repair facility check the trailer brakes, and no problems were found. Electric trailer brakes are the simple side of the braking system as the current increases it applies the trailer brakes harder and harder. So when testing the electric trailer brakes as you increase the current the magnetic force applies more force on the brake shoes. No, the brake control is where all the smarts are. So everything works towing a 2 axle trailer, no warning indicator, no fault light, it stops a double axle 10,000 lbs. trailer. When towing the trailer everything works clearance lights, brake lights, really soft stops no dash warning, hit a hard bump driving down the freeway no warning light like a loose connection. The trailer brakes stop the triple axle trailer even when the warning on the dash is on, still works as it should. The only time it displays the warning about problems with trailer wiring is when the 3 axle trailer is being towed and you applied the brakes too hard. Clear the warning and it only relights the warning if you apply the brakes too hard or due too much current is drawn to energize all 6 electric brakes at the amount of current exceeds the microprocessor pre-set limit. The brake control sees high current as a short by the microprocessor.
Ford has not informed the dealers, I have been been to 2 and their response is the factory does not help troubleshoot a customer complaint. I asked Ford to send the dealer a checklist so they can check this or that. No direction and the dealer is only looking at Go or No Go, not that the warning light turns on at this current reading. Because the microprocessor needs all these other inputs. Speed of the tires, speed of the truck, what is the throttle position at, just mashing the brake petal at a stop position is not going to give you a high enough current to cause the warning to appear. Because the truck is sitting in the test bay.
The truck and trailer will not fit in the shop bay, the current draw must be tested on the road while braking.
This would suggest one or more of your brake magnets have worn through causing a short to ground or the magnet lever shift is causing the wiring to contact ground. Did your trailer shop remove the brake drums and inspect the magnets and wiring?
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No, the solution is to reduce the current draw to the limit set by the manufacturer. That is not an arbitrary limit. It is set by the designers to be within the capability of the controller electronics and wiring gauge to ensure it functions normally with some margin for failure. Reprogramming it for a higher current trip point is not the answer. That’s like putting in a bigger fuse without changing anything else.
It is unfortunate that threshold value is not published somewhere. Obviously, as you keep adding braking elements, the current demand will go up. But what point is it designed to handle? I would expect somewhere there is a guide listing what type of trailers are suitable for this truck (and therefore maximum number of braking wheel elements).
Just because someplace looked at the trailer and deemed it OK does not make it so. The most likely source of the problem is the trailer or the connections to it. I would take Nevada_545’s advice very seriously. The magnets could easily be the issue or a wiring chafe making this trailer marginal under normal conditions. Under hard braking, it exceeds the current threshold.
The manufacturer is not going to do anything to help diagnose an application issue. To them, the system is working as designed. You need to find someone with a bit more knowledge and perseverance to find the actual fault.
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There are 2 ways to limit the current being drawn by the electric brakes. One is to put a resistor in line with each brake or disconnect a wire going to a brake or multiple brakes to reduce the total current drawn. The trailer manufacturer that built this trailer determined that this bumper pull trailer, which has a rating of GVWR is 16,000 lbs., would require 6 brakes to handle this weight. Ford’s limit for my truck is 18,000 tow weight. There are a lot of large 5th wheel trailers that only have 2 axles with 4 brakes. The 3rd axle is not needed due to a lot of weight 20% to 25% of the trailer weight being applied to the 5th wheel hitch, thereby eliminating the need for a 3rd axle. I took the trailer into a trailer repair facility to check out the braking system after the warning appeared on the dash after it happened the first time in February 2021. He checked it out from the trailer cable all the way back to each brake while doing that he repacked all 6 wheel bearings. In all the literature, Ford never has a warning about the Max number of brakes that an F-350 can handle; there are all sorts of other warnings but none on the max number of trailer brakes. The tire size on the trailer is TS235/85R16 Load Range E at 110 psi is rated at 3,100 lbs. per tire. Each trailer axle is rated for 6,000 lbs. each or Max 18,000 lbs. total axle capacity. The bigger the rim, the larger the brake drum can be, which means the brake shoes can be larger to allow the brakes to be rated to stop a 6,000 lbs. per axle. The Max weight rating for the F-350 is 11,500 lbs. with the trailer connected and the weight distribution connected. I measured the combo on a CAT scale the Steering and Drive Axles combined weight is 11,400 lbs. The truck alone is 9,340 lbs. as measured on a CAT scale. But at the same time I weighed the loaded F-350 the trailer weighed 10,360 lbs. even though the trailer is way under the GVWR 16,000 lbs. Max. The Ford OEM Brake Controller has not seen the max demand on the truck and trailer because the trailer still has 5,000 lbs. of unused capacity left. The Max GCWR for both truck and trailer is 28,700 lbs. The CAT scale showed the Gross weight of both truck and trailer to be 21,760 lbs. or almost 7,000 under Max gross weight rating. The problem is there is no way to limit what the trailer brakes draw in total, the only true control comes from the FORD OEM trailer brake controller, but FORD is not sharing those design parameters. There are other brake controllers but they cannot tie into all the trucks’ computer chips data that is available to the Ford built-in brake controller. In the good old days, the controller had a pendulum that would swing forward as the truck brakes were applied. That was before all the upgrades to the factory braking system to prevent the tires from skidding and the vehicle sliding sideways. I have talked to other trailer retail sales and they will only help with their simple brake control they sell. And of course, their system cannot tap into all the data for the numerous chips (about 100 chips) that run today’s trucks.
Would it be asking too much to have some breaks and paragraphs instead of a wall of text .
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Are you resetting the trailer brake control gain differently between the different trailers ?
The 2 extra brakes may need more or less gain than the 2 axle trailer.
About half way down the page tells you how to set the gain control
https://www.fordservicecontent.com/Ford_Content/vdirsnet/OwnerManual/Home/Content?variantid=2999&languageCode=en&countryCode=USA&Uid=G1604110&ProcUid=G1609146&userMarket=usa&div=f&vFilteringEnabled=False
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At least one other question was answered in that document:
The Ford trailer brake controller has been verified to be compatible with trailers having electric-actuated drum brakes (one to four axles) and electric-over-hydraulic brakes.
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Ford cannot and won’t verify their system works with EVERY possible brake supplier and trailer brake manufacturer. There are far too many variables. Clearly Ford is not going to fix your trailer problem since the truck works as Ford designed it…whether correct or not, it works as designed.
I see the solution as: Install an add-on under-dash trailer brake controller (accelerometers NOT a pendulum!) and wire that to feed your trailer brake system eliminating the messages…
OR Ignore the message and re-set as needed since it does not affect the operation of the brakes. It just annoys you.
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Trailer Brakes from page 291 in the 2019 SUPER DUTY Owner’s Manual
WARNING: Do not connect a trailer’s hydraulic brake system directly to your vehicle’s brake system. Your vehicle may not have enough braking power and your chances of having a collision greatly increase. Electric brakes and manual, automatic or surge-type trailer brakes are safe if you install them properly and adjust them to the manufacturer’s specifications. The trailer brakes must meet local and federal regulations. The rating for the tow vehicle’s braking system operation is at the gross vehicle weight rating, not the gross combined weight rating. Separate functioning brake systems are required for safe control of towed vehicles and trailers weighing more than 1500 lb (680 kg) when loaded.
Page 291
Super Duty (TFE) Canada/United States of America, enUSA, Edition date: 201804, Fourth-Printing Towing Integrated Trailer Brake Controller (If Equipped)
WARNING: The anti-lock brake system does not control the trailer brakes. WARNING: Use the integrated trailer brake controller to properly adjust the trailer brakes and check all connections before towing a trailer. Failure to follow this instruction could result in the loss of control of your vehicle, personal injury or death.
Note: The integrated Ford brake controller is compatible with trailers equipped with electric-actuated drum brakes and electric-over hydraulic brake systems.
Note: The integrated Ford brake controller does not control hydraulic surge-style brakes.
E183395
When used properly, the trailer brake controller assists in smooth and effective trailer braking by powering the trailer’s electric or electric-over-hydraulic brakes with a proportional output based on the towing vehicle’s brake pressure. You can adjust the amount of initial trailer brake output by selecting one of three settings through the message center.
Ford has tested the trailer brake controller to be compatible with several major brands of electric-over-hydraulic trailer brakes. Contact an authorized dealer for information on which brands you can use. The controller user interface consists of the following: A: + and - (Gain adjustment buttons):
Pressing these buttons adjusts the controller’s power output to the trailer brakes in 0.5 increments. You can increase the gain setting to 10.0 (maximum trailer braking) or decrease it to 0 (no trailer braking). Pressing and holding a button raises or lowers the setting continuously. The gain setting displays in the message center as follows:
TBC GAIN = XX.X. B: Manual control lever: Slide the control lever to the left to switch on the trailer’s electric brakes independent of the tow vehicle’s. See the following Procedure for adjusting gain section for instructions on proper use of this feature. If you use the manual control while the brake is also applied, the greater of the two inputs determines the power sent to the trailer brakes. •
Stop lamps: Using the manual control lever lights both the trailer brake lamps and your vehicle brake lamps. Trailer brake control messages appear in the information display as follows: •
TBC GAIN = XX.X NO TRAILER: Shows the current gain setting. •
TBC GAIN = XX.X OUTPUT=/ / / / / /: Displays when braking. The bars indicate the amount of power going to the trailer brakes. •
TRAILER CONNECTED: Displays when the system senses a correct trailer wiring connection. •
TRAILER DISCONNECTED: Displays when the system senses a trailer disconnection. 292 Super Duty (TFE) Canada/United States of America, enUSA, Edition date: 201804, Fourth-Printing Towing Procedure for Setting Trailer Brake Controller Effort Choose either the electric option for trailers with electromagnetic drum brakes, or the electric over hydraulic option for trailers with these brake systems.
Trailer Brake Effort Setting The trailer brake controller allows the user to customize how aggressively the trailer brakes engage. The default value is the low setting and is the recommended setting for most trailers. If your trailer’s brakes require more initial voltage, or if you prefer more aggressive trailer braking, then select either the medium or the high setting.
This adjustment does not affect the Max current being sent to the trailer brakes, only the min starting point of how much current is sent to the trailer brakes when the truck brake pedal is first depressed.
From other sources:
Electromagnet Specifications
10 and 12 Inch Brake DrumsMax Amps at 12-13 Volts
2 Brakes 7.5-8.2 amps
4 Brakes 15.0-16.3 amps
6 Brakes 22.6-24.5 amps
Individual Brake Magnet Amperage Specifications
10 and 12 Inch Brake Magnets
3.2-4.0 Max amps at 12-13 volts
Procedure for Setting Trailer Brake Controller Mode Choose the low, medium or high setting for the required initial trailer brake output. Procedure for Adjusting Gain Note: Only perform this procedure in a traffic-free environment at speeds of approximately 20–25 mph (30–40 km/h). The gain setting adjusts the trailer brake controller for the specific towing condition. You should change the setting as towing conditions change. Changes to towing conditions include trailer load, vehicle load, road conditions and weather.
The gain should be set to provide the maximum trailer braking assistance while making sure the trailer wheels do not lock when using the brakes.
Locked trailer wheels may lead to trailer instability. 1. Make sure the trailer brakes are in good working condition, functioning normally and properly adjusted. See your trailer dealer if necessary.
-
Hook up the trailer and make the electrical connections according to the trailer manufacturer’s instructions.
-
When you plug in a trailer with electric or electric-over-hydraulic brakes, a confirmation message appears in the information display.
4. Use the gain adjustment (+ and -) buttons to increase or decrease the gain setting to the desired starting point. A gain setting of 6.0 is a good starting point for heavier loads.
-
In a traffic-free environment, tow the trailer on a dry, level surface at a speed of 20–25 mph (30–40 km/h) and squeeze the manual control lever completely.
-
If the trailer wheels lock up, indicated by squealing tires, reduce the gain setting. If the trailer wheels turn freely, increase the gain setting. Repeat Steps 5 and 6 until the gain setting is at a point just below trailer wheel lock-up.
If towing a heavier trailer, trailer wheel lock-up may not be attainable even with the maximum gain setting of 10.
Information Display Warning Messages Note: An authorized dealer can diagnose the trailer brake controller to determine exactly which trailer fault has occurred. However, your Ford warranty does not cover this diagnosis if the fault is with the trailer. TRAILER BRAKE MODULE FAULT Displays in response to faults sensed by the trailer brake controller, accompanied by a single tone. If this message appears, contact an authorized dealer as soon as possible for diagnosis and repair. The controller may still function, but with degraded performance. WIRING FAULT ON TRAILER Displays when there is a short circuit on the electric brake output wire. 293 Super Duty (TFE) Canada/United States of America, enUSA, Edition date: 201804,
Fourth-Printing Towing If this message displays, with no trailer connected, the problem is with your vehicle wiring or trailer brake controller. Contact an authorized dealer. If the message only displays with a trailer connected, the problem is with the trailer wiring. Consult your trailer dealer for assistance. This can be a short to ground (such as a chaffed wire), short to voltage (such as a pulled pin on trailer emergency breakaway battery) or the trailer brakes may be drawing too much current. Points to Remember Note: Do not attempt removal of the trailer brake controller without consulting the Workshop Manual. Damage to the unit may result. •
Adjust gain setting before using the trailer brake controller. •
Adjust gain setting, using the procedure above, whenever road, weather, trailer or vehicle loading conditions change from when the gain was initially set. •
Only use the manual control lever for proper adjustment of the gain during trailer setup. Misuse, such as application during trailer sway, could cause instability of trailer or tow vehicle. •
Avoid towing in adverse weather conditions. The trailer brake controller does not provide anti-lock control of the trailer wheels. Trailer wheels can lock up on slippery surfaces, resulting in reduced stability of trailer and tow vehicle. •
The trailer brake controller is equipped with a feature that reduces output at vehicle speeds below 11 mph (18 km/h) so trailer and vehicle braking is not jerky or harsh.
This feature is only active when applying the brakes using your vehicle’s brake pedal, not the controller. •
The controller interacts with the brake control system and powertrain control system of your vehicle to provide the best performance on different road conditions. •
Your vehicle’s brake system and the trailer brake system work independently of each other. Changing the gain setting on the controller does not affect the operation of your vehicle’s brakes. •
When you switch the engine off, the controller output is disabled and the display and module shut down. Trailer Lamps WARNING: Never connect any trailer lamp wiring to the vehicle’s tail lamp wiring; this may damage the electrical system resulting in fire. Contact your authorized dealer as soon as possible for assistance in proper trailer tow wiring installation. Additional electrical equipment may be required. Trailer lamps are required on most towed vehicles. Make sure all running lights, brake lights, turn signals and hazard lights are working. Before Towing a Trailer Practice turning, stopping and backing up to get the feel of your vehicle-trailer combination before starting on a trip. When turning, make wider turns so the trailer wheels clear curbs and other obstacles.
I think your problem has to do with the trailer and not the truck. did you check out the magnets as Nevada_545 mentioned? I would also look at all the wiring for chaffing or a break.
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