Car jerks when letting off brake

One thing that I have found that can make a P2 or P3 jerk in city traffic.

Both controllers have what is called a Hold function. Hold is activated when the brake light on the TV is on for more than 5 seconds and there is no active deceleration. The Hold function applies 25 percent of the full voltage that has been set into the controller.

This can happen if you have your foot on the brake with only enough pressure to activate the brake light but with little or no active braking.

I do this often in city traffic when I am anticipating having to stop for a red light or another vehicle.

When I feel the Hold function activate I just take my foot off the brake for a second or two. This will cause the jerk feeling described by the OP.

Another time this comes into play is backing a trailer into a parking slot. Sometimes I just remove the 7 way while parking the trailer. Also makes it easier to back onto leveling blocks as often the Hold function will come into play before I am on the blocks.

If the Hold function does come into play before getting on the leveling blocks it can cause the wheel to skid the block instead of climbing onto the block.

Truth is. With a good controller. Your TV and trailer should stop as one. No jerking, no pull from the trailer. you should not even notice the trailer brakes come on, or go off.

My Prodigy achieves this great braking action. I can't even tell it comes on. But I know the TT brakes are working, because I can hear the Tt tire cry under heavy braking.

Now with the factory controller in my truck. I have the same action. So no. Quality controllers do NOT jerk in town or on the highway. IF your trailer brakes jerk in town. you have the wrong controller, OR you have the gain set way too high.

Klohey wrote:
Had the same problem. Solved it. Prodigy P2 brake control. I had unknowingly pressed the BOOST BUTTON on the top of the control. That was the culprit. Reset it and no more "jerking" when releasing the brake pedal.

Which IS the exact reason I did not consider a P2 and a P3 at that time did not exist.

Too many buttons and settings that either need attending to while driving or when driving conditions change.

That is one of the biggest issues I see with pretty much all controllers that depend on your brake light to signal the controller to start braking (ALL inertial controllers use the brake light which is the same as a time based controller).

Time based AND inertial controllers REMOVE the brake output as soon as the brake lights turn off.. No ramp down, just a straight OFF.

That results in the trailer pushing you when stopped on hills, effect gets worse in stop and go traffic.. Some times you might be on/off the brake quickly in stop and go and Inertial controllers may or may not "detect" or react fast enough and the result is jerky feeling.. The BOOST setting is supposed to HIDE that feeling..

My Jordan 2020 was dead on simple, sure you had some initial "setup" to do and was not a "plug and play" device, but once you had it dialed in there was no other knobs other than the output knob, no switches or other do-dads to tinker with. That controller was smooth as silk and not once ever gave a jerky feel under slow speed, stop n go or even highway conditions.

I was a bit nervous when I bought my 2013 F250 with IBC, was not sure if it would result in just as good feel as my Jordan.. I was extremely pleased the first trip on how smooth the IBC was.. Could not tell the difference and the transition to IBC was a smooth one.

I still have the Jordans in my older vehicles, but, if I sell those vehicles they WILL be stripped of the Jordans!

Keeping them as backup just in case the IBC were to fail. You WILL have to pry the Jordans out of my cold dead hands.

Had the same problem. Solved it. Prodigy P2 brake control. I had unknowingly pressed the BOOST BUTTON on the top of the control. That was the culprit. Reset it and no more "jerking" when releasing the brake pedal.

temccarthy1 wrote:

oyarsa wrote:
We are heading on our maiden voyage!

I have a 2012 Toyota Sequioa pulling a 2017 Bullet 247BHSWE. I of course have a brake controller installed, but I'm struggling with getting it properly adjusted. The car is jerking a lot when I let off the breaks. This is particularly annoying in town. If I lower the gain, I can get rid of the jerking, but at that low the trailer breaks don't feel like they're doing much. If I just use the paddle it doesn't slow us down very well. I've tried adjusting the sync, which seemed to help, but only modestly.

Should I expect it to be smooth when releasing the break, or just get used to the jerking?

The jerking you feel is normal in slow moving heavy traffic when you are constantly stopping and starting at lights. Just dial down your controller until it stops the jerking movement(1-3). It will not be a stopping problem when you are generally going 25 mph or less. When you get back to open areas and highway speeds, just dial the controller back up to mid range (5-7). It will make the stop starts much more comfortable! Try it! Works for me every time! I read about it on a blog like this! Hope it helps!

NO, NO, NO!

That jerking is not "normal" at all IF you have a GOOD QUALITY BRAKE CONTROLLER!

The jerking comes from CHEAP INFERIOR ENTRY LEVEL CONTROLLERS which are no better than turning a light switch on and off.

I made ONE trip with a cheap time based controller and quickly decided that spending MORE on the BEST controller I could find was number one priority.

I studied long and hard and decided on the Jordan Ultima 2020 which used a stainless aircraft wire connected from the brake pedal to the controller.. That cable actuated a sensor inside the controller which controlled the output instead of relying on timers, micro computers and firmware..

Skipped right over the all of the simulated controllers like the Voyager, P2 and P3 series and went straight to something the DIRECTLY interfaced to the vehicle.

The result is a set and forget controller, I NEVER had to readjust for ANY different driving condition.

That feature alone I can say HAS saved my bacon several times when driving 65 mph and having DEER cross in front of me :E , under emergency situations like that you DO NOT HAVE TIME to fiddle with a brake controller settings!

At that time I bought the Jordans they only cost a mere $10 more than a P2 but to me that extra $10 saved me THOUSANDS of dollars in damages TWICE!

Sadly, Jordan is out of business and finding direct controllers is a difficult and expensive task..

There is only one now days and it connects via the OBDII diagnostic port of your vehicle, it is expensive at around $325 but it WILL operate as smooth as a IBC (factory integrated controller).

DIRECLINK BRAKE CONTROLLER

If you don't wish to spend that kind of money, then at least go to a P3, that is the most advanced inertia controller on the market and should result in a fairly smooth drive without the need for constant baby sitting of the controller.

time2roll wrote:
Reese Brakeman can be several different including timed and digital.

SoundGuy wrote:
There are currently 2 Reese Brakeman Controllers and both are timed, not inertia ... unquestionably this is the OP's issue. Remove it and invest in a Tekonsha P2 or P3 and your problem will be solved, assuming the brakes themselves are properly adjusted, which they should be on a trailer this new. If after installing a P2 or P3 you find the brakes are still grabbing at low speeds they may need to be adjusted OR as I did you may have to have a dealer tech chamfer the leading edges of each brake shoe - that will absolutely eliminate any grabbing.

captnjack wrote:
I think you are going to the most difficult solution before trying the simpler more obvious solution. Just adjust the brake controller itself.

If you bothered to read what I actually wrote you would (or should) realize I did not "go to the most difficult solution before trying the simpler more obvious solution" but rather did suggest multiple steps that could be taken to resolve this issue, starting with the simplest - replace the time based controller with an inertia based. :S

As far as chamfering the brake shoes is concerned, this is a technique used by many techs that will absolutely correct chattering or grabbing when the brakes are applied when no other solution will. It's also the solution I used on my own trailer to solve this exact problem the OP is complaining about.

Keep your foot on the brake til u stop. (I save time by writing u etc) It won't jerk. At least they work.

No woman ever falls in love with a man unless she has a better opinion of him than he deserves.

SoundGuy wrote:

time2roll wrote:
Reese Brakeman can be several different including timed and digital.

Need the actual model number but I think you will soon be looking at a Prodigy P2 or P3.

There are currently 2 Reese Brakeman Controllers and both are timed, not inertia ... unquestionably this is the OP's issue. Remove it and invest in a Tekonsha P2 or P3 and your problem will be solved, assuming the brakes themselves are properly adjusted, which they should be on a trailer this new. If after installing a P2 or P3 you find the brakes are still grabbing at low speeds they may need to be adjusted OR as I did you may have to have a dealer tech chamfer the leading edges of each brake shoe - that will absolutely eliminate any grabbing.

I think you are going to the most difficult solution before trying the simpler more obvious solution. Just adjust the brake controller itself. My prodigy has an adjustment lever, don't they all? MAYBE his brakes will need adjusting but I'd steer clear of "chamfering" the brake shoes. I just don't think it would be necessary. Like shooting a rabbit with an elephant gun, isn't it?

time2roll wrote:
Reese Brakeman can be several different including timed and digital.

Need the actual model number but I think you will soon be looking at a Prodigy P2 or P3.

There are currently 2 Reese Brakeman Controllers and both are timed, not inertia ... unquestionably this is the OP's issue. Remove it and invest in a Tekonsha P2 or P3 and your problem will be solved, assuming the brakes themselves are properly adjusted, which they should be on a trailer this new. If after installing a P2 or P3 you find the brakes are still grabbing at low speeds they may need to be adjusted OR as I did you may have to have a dealer tech chamfer the leading edges of each brake shoe - that will absolutely eliminate any grabbing.

My controller needs tweaking almost every trip. It is not the controller it is me.

On the road I like a more positive brake grab. However it is annoying in city traffic so I back off a bit. I do like to feel a little tug when I brake but not so it is annoying.

Temperature and moisture also play a part but the biggest issue is perception. More than once I have had the controller adjusted just perfect only to have it seem grabby or light the next time.

I am sure that some of the variation comes from the controller, TT brakes and other variables but the rest of the variation comes from my incessant diddling until I have decided it is good enough till the next trip.

I will say that in the emergency stops I have had, once for deer and once for another car. The controller worked just fine.