Parking Brake unexpected Release (MT)

[Spart]

I said I wasn't going to comment. But I think I will because.. safety.

I went for a test drive in an MT today and I attempted to get the parking brake to fail. After I switched off the engine and applied the park brake I mashed the pedals, put it in gear, engaged the clutch, etc. Park brake didn't flinch.

Might be some cars are Friday built?

Perhaps BMW/Toyota are under the understanding that this feature is not allowed by regulation in AU. If you set the parking brake, then try to drive away in first gear and it doesn't release, then the feature is not active.

Cars delivered in different markets may be identical in all respects (even FW versions) save for subtle changes to configuration settings that are normally locked away unless you have a fancy dealership scan tool. These configuration settings tell the firmware how to act and what features to enable or disable.

Ford calls this configuration "As-Built" and you can configure it yourself with a piece of third-party software called FORscan. For FCA vehicles, you have AlfaODB. For BMW vehicles and the Supra, you have BimmerCode. And so on...

If anything, this might hint that the feature could be disabled through BimmerCode if only we knew where to look. With Fords, you are able to download complete As-Built configuration files by VIN and sus out the subtle differences to figure out how to disable features. I'm not sure any such method exists for BMWs.

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[Spart]

All the reported cases are with the car on; such as leaving the car running to defrost.

Valid point, @lmfao failed on step one:

I believe that it can be replicated 100% of the time if you do the following, in order:

• Engine running, transmission in neutral.
• Set parking brake.
• Hold clutch pedal in.
• Touch brake pedal and release.
• Touch throttle pedal and release.
• Wait ten seconds or so.
• Release clutch pedal.

 

[RyanA90]

I thought something was wrong with me when this happened.

-Car is parked in 1st gear
-Shift to N
-Clutch In
-Start Car
-Once I let off the clutch, the parking brake releases

I've gotten used to it that once the PB releases I engage it again....annoying

 

[6mtsoup]

I thought something was wrong with me when this happened.

-Car is parked in 1st gear
-Shift to N
-Clutch In
-Start Car
-Once I let off the clutch, the parking brake releases

I've gotten used to it that once the PB releases I engage it again....annoying

You don’t clutch in to move to neutral…..? I do the exact same thing except clutch to move the shifter and never happened once?‍

 

[RyanA90]

You don’t clutch in to move to neutral…..? I do the exact same thing except clutch to move the shifter and never happened once?‍

Not when the car is off.

 

[Spart]

I attempted to engage with Toyota BEC about this issue.

The person they assigned to my case didn't seem to understand the issue, repeatedly tried to pawn me off on a dealer, referred me to pages in the owner's manual, and stated the car is working as designed.

I got the impression that she is someone who has never seen a manual transmission car in real life, and probably doesn't understand why a person would use the parking brake and not just put the car in P.

If anyone else that has had this issue cares to take the time, you might try to start a request with them here:

https://support.toyota.com/s/questions-comments

Perhaps - and this is likely luck of the draw - you will have someone assigned to your case that both understands the importance of a parking brake on a manual transmission car and the danger-to-life-and-limb hazard of a manual transmission car with a malfunctioning parking brake.

I really just don't want to see one of these cars roll away out of control and hit someone. I personally understand how to work around the issue, but that does nothing for the hundreds (soon thousands?) of other MT Supra owners out there who are unaware.

 

[FLtrackdays]

Could be why so many people are moving to Florida ? Being flat here… Sorry, really bad joke.

Here’s a cheap fix (cheaper than the wind buffeting things):

https://www.harborfreight.com/solid-rubber-wheel-chock-96479.html

 

[Spart]

I've submitted a complaint to NHTSA and when that complaint becomes public on their website, I think I will start a new thread asking for MT folks to "me-too" the issue on their site.

Either I misunderstood, or NHTSA provided incorrect info about the ability to me-too an issue, or their timelines are seriously out of whack.

I would encourage anyone who can replicate this issue to report it to NHTSA here: https://www.nhtsa.gov/report-a-safety-problem

As I previously mentioned, Toyota BEC has been contacted and they were unsympathetic. That avenue seems like a complete waste of time, but if you'd like to just document that you tried for your own peace of mind, you can do so here: https://support.toyota.com/s/questions-comments

Again, the steps to replicate this are as follows:

I believe that it can be replicated 100% of the time if you do the following, in order:

1. Engine running, transmission in neutral.
2. Set parking brake.
3. Hold clutch pedal in.
4. Touch brake pedal and release.
5. Touch throttle pedal and release.
6. Wait ten seconds or so.
7. Release clutch pedal.

Why in this order? I believe that this system is armed as soon as the parking brake is applied, and at that point it starts tracking whether the brake and gas have been recently applied. "Recent" is overly liberal though, and this interlock should really be looking at simultaneous clutch release and throttle applied IMO. In addition to an interlock that defeats the system if the car is in neutral.

And if you need some visuals to go along with that, check out this video:

 

[FLtrackdays]

Either I misunderstood, or NHTSA provided incorrect info about the ability to me-too an issue, or their timelines are seriously out of whack.

I would encourage anyone who can replicate this issue to report it to NHTSA here: https://www.nhtsa.gov/report-a-safety-problem

As I previously mentioned, Toyota BEC has been contacted and they were unsympathetic. That avenue seems like a complete waste of time, but if you'd like to just document that you tried for your own peace of mind, you can do so here: https://support.toyota.com/s/questions-comments

Again, the steps to replicate this are as follows:



And if you need some visuals to go along with that, check out this video:

Wow!!!!! 3 minutes in, this is unbelievable ?. Thanks for making this more understandable to the masses. That is just plain awful! And as you said, needs to be fixed ASAP ?

Great job ?? @Spart . What are you supposed to do? Carry wheel chocks with you everywhere you go????

 

[RyanA90]

I think i figured out how to not make it release.
Keep your driver door open when normally starting your car.

 

[Kroberter]

I have a service appointment next week and I plan on replicating the issue for them to witness. I saw the complaint on nhtsa but I couldn’t figure out how to add myself to the concerned owner list. Does rolling in to a parking block without anyone in the car count as a crash? My anxiety was cranked to 11 when I found my car 5 feet further into a parking spot than I left it.

 

[Spart]

I saw the complaint on nhtsa but I couldn’t figure out how to add myself to the concerned owner list. Does rolling in to a parking block without anyone in the car count as a crash? My anxiety was cranked to 11 when I found my car 5 feet further into a parking spot than I left it.

Definitely go ahead and submit your own complaint.

 

[Jmanlevan]

I hate that the electric parking brake auto releases for you in general, even when you intentionally put it in gear to start driving. It should only disengage when you physically press the button to intentionally disengage it. If you have the parking brake engaged and you have the car in gear to start driving away without physically disengaging it by pressing the button, the parking brake should remain engaged and your car should just rev without you going anywhere. As a result, making you look stupid, just like it would if it had an old school, emergency brake lever that gets pulled up and was left up by accident because you forgot to lower it before driving off.

Electronic technology isn't always better. Sometimes physical, manual methods of things just work better and are more reliable. Parking brakes and Transfer case selectors are two of these things that should always be physical, not electronic in my opinion. Really wish Toyota would have placed an old school emergency brake lever in this car instead of the electronic one.

 

[lucky phil]

What happens if you take the clutch out THEN apply the park brake, then release the pedal brake?

No one is brave enough to say it, but this always leaving the car in gear when parked thing is nonesense - leaving the car in a high gear (with the wheels pointed towards the curb) only applies when parked on a steep incline.

Sorry disagree. Since day 1 I've always parked a manual in gear, first gear. Flat ground, sloping ground, in the street or in the garage always in gear. Why would you not? Why would you rely on 1 system only to make sure the car stays where it's put? It's like people that don't use the handbrake on an auto and rely on the Park position.
When we park aircraft we set the park brake and chock the wheels, same principle, never rely on a single system for safety. It's a no brainer really.
Same as start the car and then do what....fill out your tax return? After I start the car I drive the car and if I'm not driving the car and messing about with something else such as the nav system which I tend not to do in most cases my foot is on the brake. If the engine is running and I'm not moving then my foot is on the brake. I never get out of a running car and trust the handbrake even moving my cars around. If I'm not in the car the engine is off and the PB is set. If I'm working on the car and I need the engine running then the car is in neutral the park brake is set and the wheels are chocked. When I get in the drivers seat and start the car I'm there to drive it not go on social media or do my hair or pick my nose or check my look in the mirror. Drive, I'm there to drive.
Phil

 

[NocturnalEmber]

Sorry disagree. Since day 1 I've always parked a manual in gear, first gear. Flat ground, sloping ground, in the street or in the garage always in gear. Why would you not? Why would you rely on 1 system only to make sure the car stays where it's put? It's like people that don't use the handbrake on an auto and rely on the Park position.
When we park aircraft we set the park brake and chock the wheels, same principle, never rely on a single system for safety. It's a no brainer really.
Same as start the car and then do what....fill out your tax return? After I start the car I drive the car and if I'm not driving the car and messing about with something else such as the nav system which I tend not to do in most cases my foot is on the brake. If the engine is running and I'm not moving then my foot is on the brake. I never get out of a running car and trust the handbrake even moving my cars around. If I'm not in the car the engine is off and the PB is set. If I'm working on the car and I need the engine running then the car is in neutral the park brake is set and the wheels are chocked. When I get in the drivers seat and start the car I'm there to drive it not go on social media or do my hair or pick my nose or check my look in the mirror. Drive, I'm there to drive.
Phil

Feel free to agree to disagree is my opinion. I've always left my cars in neutral from day 1 and used the e-brake. Unless its loose or in poor condition, there's no real reason to suspect it would fail. Not saying it can't or won't fail, but I don't believe the chances are high enough to warrant concern assuming its operating properly. I'd say the biggest risk for me is when someone drives my car that does leave it in gear, if I don't check I've had past cars lunge forward momentarily because I don't assume they are in gear, over the years I've gotten more diligent about checking that though.

But back on topic, my car has never done this, and its' a factory six speed manual as well. In fact, I've noticed if I pull into a parking spot and change my mind and decide to inch up further, sometimes the car holds the brakes for me when I feel it shouldn't, almost like the hill start assist is operating.

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