Trailer brake not working

[ocropper]

For those who have been waiting for some movement on this issue, Ford has released a software update to the brake controller module (TRM). I saw it on FDRS yesterday and installed it. I have no idea whether the update will correct the random brake disconnects until I get my trailer out in about three weeks to do some testing. But, so far, the early reports I’ve heard are that it corrects a false DTC that some people were experiencing. I never had that problem so I can’t verify. I haven’t heard reports of any other fixes. But it’s still early and not much testing beyond the installation itself has been done.

This is the one the dealer told me was coming when I got my truck out for the recall driveshaft repair. Since it’s intermittent it will be hard to verify but I certainly will ask them to apply. By the way - they said tge reverse brake assist error message many of us got after taking tailgate off for bed spray will get fixed soon via OTA update.

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[JEB]

This is the one the dealer told me was coming when I got my truck out for the recall driveshaft repair. Since it’s intermittent it will be hard to verify but I certainly will ask them to apply. By the way - they said tge reverse brake assist error message many of us got after taking tailgate off for bed spray will get fixed soon via OTA update.

I had heard that, but Ford has a different understanding of “soon” than most people with more than a rudimentary command of the English language.

 

[UGADawg96]

I've been watching this thread for a while. I have a Grand Design Imagine, not an Airstream. I've towed this trailer on a few trips with various trucks and a couple times with my powerboost too. Never had a problem until yesterday when playing with the trailer light test in the FordPass app. I think it broke my truck. Or was it just the universe claiming coincidence. Doubt it.

Our standard pre-trip inspection is to walk around the trailer, double check hitch, check trailer lights, and then do a pull test before departing. I define a pull test as having the truck in drive, taking foot off brake, and as the truck and trailer start to creep forward, apply the trailer brake controller to verify its operational. I did a walk around to check running lights and all was good. I was not able to do the blinker and brake test at that time. I did the pull test and the brake controller worked as expected. I drove maybe a mile and decided to stop and use the trailer light check. Using the app, initiated the test. After seeing each blinker and brake application work, I stopped the test. There was a message on the 12" center console screen that said trailer light check stopped unexpectedly. Weird. I did another pull test, but this time, it didn't work. The message on the dash said gain set to 6.5, no trailer. It did not engage the trailer brakes. I went into the 12" screen and it showed the active trailer. Next I did the trailer light check from the 12" screen versus the app. Start the test, watched the lights, stopped the test. Error pop up again that the test was stopped unexpectedly. Weird again. I powered off the truck, reset the 7pin cable. Started truck. No fix. It showed the active trailer, but the brake controller didn't work. I powered off the truck, left the 7pin unplugged, powered the truck on, reinserted the 7pin. The 12" screen said trailer detected and asked me to select a saved trailer. Went to test the brake controller again, same issue, gain set to 6.5, no trailer. WTF.

When driving and applying the brake pedal, it doesn't feel any different stopping than when the brake controller was working. So my question is does this mean the trailer brakes are working when applying the brake pedal and just not the controller or do I not have any trailer brakes if the controller doesn't work by itself. WTF.

 

[JEB]

I've been watching this thread for a while. I have a Grand Design Imagine, not an Airstream. I've towed this trailer on a few trips with various trucks and a couple times with my powerboost too. Never had a problem until yesterday when playing with the trailer light test in the FordPass app. I think it broke my truck. Or was it just the universe claiming coincidence. Doubt it.

Our standard pre-trip inspection is to walk around the trailer, double check hitch, check trailer lights, and then do a pull test before departing. I define a pull test as having the truck in drive, taking foot off brake, and as the truck and trailer start to creep forward, apply the trailer brake controller to verify its operational. I did a walk around to check running lights and all was good. I was not able to do the blinker and brake test at that time. I did the pull test and the brake controller worked as expected. I drove maybe a mile and decided to stop and use the trailer light check. Using the app, initiated the test. After seeing each blinker and brake application work, I stopped the test. There was a message on the 12" center console screen that said trailer light check stopped unexpectedly. Weird. I did another pull test, but this time, it didn't work. The message on the dash said gain set to 6.5, no trailer. It did not engage the trailer brakes. I went into the 12" screen and it showed the active trailer. Next I did the trailer light check from the 12" screen versus the app. Start the test, watched the lights, stopped the test. Error pop up again that the test was stopped unexpectedly. Weird again. I powered off the truck, reset the 7pin cable. Started truck. No fix. It showed the active trailer, but the brake controller didn't work. I powered off the truck, left the 7pin unplugged, powered the truck on, reinserted the 7pin. The 12" screen said trailer detected and asked me to select a saved trailer. Went to test the brake controller again, same issue, gain set to 6.5, no trailer. WTF.

When driving and applying the brake pedal, it doesn't feel any different stopping than when the brake controller was working. So my question is does this mean the trailer brakes are working when applying the brake pedal and just not the controller or do I not have any trailer brakes if the controller doesn't work by itself. WTF.

I have not before seen any kind of connection between the trailer light test and the brake controller but it is interesting. First thing is to get your brake controller working again and showing a connection. Don’t bother screwing with the 7-way plug. I’m pretty sure the physical connection has nothing to do with this issue. If you see no connection when you manually activate the brake controller, pull over as soon as you can and turn off the truck. Open and close the door. Leave the truck if you can. If you can’t, just sit there and don’t touch anything. Wait 10-15 minutes. You want all the relays to reset and the truck to fully power down. You’ll start to hear some clicks. You know the truck is powered down when the LED halo around the USB ports in the rear seat console area is out. Then start the truck back up normally and see if you have connected trailer brakes by again manually activating the brake controller.

Regardless of feel, which can be deceiving, the only way to know you are reconnected electrically is to squeeze the manual controller. If a screen pops up and you can see the brake intensity bar going up as you apply the manual control, you are reconnected. If it feels ok but you don’t see this pop up behavior, I wouldn’t trust the connection. Try again to reset.

 

[UGADawg96]

I have not before seen any kind of connection between the trailer light test and the brake controller but it is interesting. First thing is to get your brake controller working again and showing a connection. Don’t bother screwing with the 7-way plug. I’m pretty sure the physical connection has nothing to do with this issue. If you see no connection when you manually activate the brake controller, pull over as soon as you can and turn off the truck. Open and close the door. Leave the truck if you can. If you can’t, just sit there and don’t touch anything. Wait 10-15 minutes. You want all the relays to reset and the truck to fully power down. You’ll start to hear some clicks. You know the truck is powered down when the LED halo around the USB ports in the rear seat console area is out. Then start the truck back up normally and see if you have connected trailer brakes by again manually activating the brake controller.

Regardless of feel, which can be deceiving, the only way to know you are reconnected electrically is to squeeze the manual controller. If a screen pops up and you can see the brake intensity bar going up as you apply the manual control, you are reconnected. If it feels ok but you don’t see this pop up behavior, I wouldn’t trust the connection. Try again to reset.

Yesterday I was picking up the trailer from service and taking back to our storage unit and it was getting late. It was about a 20 mile drive. After messing with it for a bit, I just drove a bit slower and dropped it off at storage and returned home. I don't know when I'll get back down there to retest, but the truck sat overnight outside, so hopefully everything reset. Not sure if I'll get back to it until next weekend. If that's the case, then that will be at least 7 nights powered off for at least 10 hours each, well more than the suggested 10-15min.

 

[JEB]

Yesterday I was picking up the trailer from service and taking back to our storage unit and it was getting late. It was about a 20 mile drive. After messing with it for a bit, I just drove a bit slower and dropped it off at storage and returned home. I don't know when I'll get back down there to retest, but the truck sat overnight outside, so hopefully everything reset. Not sure if I'll get back to it until next weekend. If that's the case, then that will be at least 7 nights powered off for at least 10 hours each, well more than the suggested 10-15min.

Don’t be surprised if you see a failed connection the first time you start up with the trailer connected. Because you disconnected and drove away from storage, reconnecting again when you get back to storage is a new event the truck has to process. Just turn it off again, wait 10-15 minutes, and start back up.

 

[UGADawg96]

Don’t be surprised if you see a failed connection the first time you start up with the trailer connected. Because you disconnected and drove away from storage, reconnecting again when you get back to storage is a new event the truck has to process. Just turn it off again, wait 10-15 minutes, and start back up.

Would you suggest plugging in the trailer with the truck off or on ?

 

[JEB]

Would you suggest plugging in the trailer with the truck off or on ?

I don’t think it matters. It hasn’t for me. In my experience, the problem has nothing to do with the physical connection and there’s no magical order to how you hook things up. There’s no magical grease. Watching the truck start up over the last several months, my theory is that the truck is having problems loading and running all of its internal software cleanly due to a combination of buggy software and limited processing power. Start-up is the biggest problem. A good analogy is your PC. I’m sure you’ve had circumstances where you booted up your PC and found that not all of your start-up programs loaded properly. You fixed it by turning it off and rebooting.

I think the exact same thing is happening to the truck. The last time I saw a disconnect, it occurred at start up and the truck looked like it has laboring to load too many things at once. Sure enough, the trailer brake controller failed to recognize the trailer brake connection. Upon further consideration, it’s not all that surprising. The truck has over 30 separate modules (mine has 35), each of which loads its own software. All of them might not load correctly all of the time.

My hope is that, as Ford continues to release updates to all of the module software, including but not limited to the TCM, it will all load and run more smoothly and take better advantage of the limited on-board computing power. We’ll see. But to help test the theory, I bought a programmer and a few 2-day FDRS licenses and I’m updating all module software as Ford releases it, including modules that aren’t being updated OTA via Power-Up releases.

I still thing the most likely culprit is a bug in the TCM software. But many of the modules in these trucks are out of date. It’s certainly not making things any easier on the truck’s limited processing capabilities.

And before you ask, no, your dealer will not update software for you just because it’s out of date. Ford won’t reimburse the dealer for it. A dealer will update your software only if you can tie a specific complaint to a specific out of date piece of software.

 

[wayne b]

You’ll start to hear some clicks. You know the truck is powered down when the LED halo around the USB ports in the rear seat console area is out. Then start the truck back up normally and see if you have connected trailer brakes by again manually activating the brake controller.

This is a useful bit that I was not aware of before, re: LED halo. thanks!

I don’t think it matters. It hasn’t for me. In my experience, the problem has nothing to do with the physical connection and there’s no magical order to how you hook things up. There’s no magical grease. Watching the truck start up over the last several months, my theory is that the truck is having problems loading and running all of its internal software cleanly due to a combination of buggy software and limited processing power. Start-up is the biggest problem. A good analogy is your PC. I’m sure you’ve had circumstances where you booted up your PC and found that not all of your start-up programs loaded properly. You fixed it by turning it off and rebooting.

Interesting (and informed) post, curious if you think having the truck already booted up and then plugging the 7-pin and selecting trailer is going to lower the chances of this happening?

 

[JEB]

This is a useful bit that I was not aware of before, re: LED halo. thanks!




Interesting (and informed) post, curious if you think having the truck already booted up and then plugging the 7-pin and selecting trailer is going to lower the chances of this happening?

I tried that method. Didn’t make a difference. It would work a few times, and just when I thought I was home free with a new, surefire method, it would fail. Ultimately, from a failure rate perspective it proved no more reliable than starting the truck with the trailer already connected.

The only method that has proven reliable for me is to make sure I check the connection before pulling away. If it’s not connected, I shut completely down and restart. Annoying as it is, it’s the only reliable method I’ve found.

 

[tderouchie]

Yesterday I was picking up the trailer from service and taking back to our storage unit and it was getting late. It was about a 20 mile drive. After messing with it for a bit, I just drove a bit slower and dropped it off at storage and returned home. I don't know when I'll get back down there to retest, but the truck sat overnight outside, so hopefully everything reset. Not sure if I'll get back to it until next weekend. If that's the case, then that will be at least 7 nights powered off for at least 10 hours each, well more than the suggested 10-15min.

My method is to disconnect the truck battery for 2-3 minutes and start over. It has been successful every time until I need to turn the truck off , at which point i will disconnect the battery again before resuming my trip.

 

[JEB]

My method is to disconnect the truck battery for 2-3 minutes and start over. It has been successful every time until I need to turn the truck off , at which point i will disconnect the battery again before resuming my trip.

This method does not work with a Powerboost, because of the 12V auxiliary battery and because it can mess up the battery monitoring system. If you have a Powerboost, do not do this.

 

[tderouchie]

This method does not work with a Powerboost, because of the 12V auxiliary battery and because it can mess up the battery monitoring system. If you have a Powerboost, do not do this.

Good to know! Thank you. My 2022 is arriving within the next week or two, so hopefully this won’t be an issue.

 

[tmdaley]

I also have this trailer brake problem, and just found this thread. I have a 2021 HEV F150 and pull a ~3500 lbs Escape trailer. I have had two occurrences of the brakes not working, one started working while towing and the other started after a fuel stop (and shutdown/restart).

 

[fluffernutter]

For those having issues, do you have this connector on your trailer plug (‘dual blade’):

Or do you have this one (‘single blade’):

My FIL has a GMC Sierra and RAM 2500 and he noted both gave him the same intermittent connectivity issues with the ‘dual blade’ plug until he cut the wire and used the ‘single pin’ connector as he said you can’t really jam the plug in fully so it loses connection when driving along. Curious if this is the same fix here (as wayne b had posted this earlier and put this link: http://www.rambodybuilder.com/2016/docs/ram/TrailerConnCompat.pdf )

The female on the truck may just be expecting the single blade in order to make a reliable connection. If so, swapping out a new connector on the trailer plug side hopefully is a fix.