David Noland suggests Model S pedal placement is a safety hazard

[liuping]

The brake pedal should be at least 1/4" above the gas pedal.

My brake pedal is at least an inch higher than the accelerator pedal. Maybe p85s have less of a difference?

 

[artsci]

Looks like a bad master cylinder or leaking brake line to me.

For sure. There's something wrong if the brake pedal goes that far in to the floor. I wouldn't even drive this car until it's diagnosed and fixed. Dangerous for sure. Is it Tesla's fault? Hard to assign blame in these circumstances.

 

[andrewket]

Over the course of a year of ownership I've occasionally pressed both the brake and the accelerator at the same time. I get the bonk and warning banner across the screen.

It happened to me twice this past week and once it almost caused an accident. I was coming to a stop behind a car at a stop light. I was traveling maybe 2mph when the car lurched forward a bit. I managed to stop right as I heard the bonk and the saw the banner.

I have no data or theories on cause. I'm sharing just to say there is something here worth further investigation.

 

[JRP3]

Anyone with a 3d printer want to try and fab a thicker brake pedal cover? Build it up an extra 1/4-1/2 inch or so and see if that makes a difference.

 

[Liz G]

Just FYI, in many jurisdictions (e.g. here) it is illegal to drive without shoes on. Get some ballet slippers or something...

What is the rational behind that? I Drive with no shoes all the time and can't imagine why it would be more dangerous than with shoes. Actually I think it's safer cause I can feel the pedal and can control speed better with my toes.

 

[Doug_G]

What is the rational behind that? I Drive with no shoes all the time and can't imagine why it would be more dangerous than with shoes. Actually I think it's safer cause I can feel the pedal and can control speed better with my toes.

I was taught this back when and accepted it as gospel. But I recently read the Ontario Highway Traffic Act to confirm, and despite what I was taught, the section only applies to horses! LOLZ.

 

[EarlyAdopter]

Looks like a bad master cylinder or leaking brake line to me.

Plus the guy posting the video is going crazy in the comments, obviously trying to drum up FUD.

Hmmm, the poster of that video, "Keef Wivaneff", refers to Tesla as "Terdsla" in the comments. Me thinks he is not the owner of that car.

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Yeah. His proof is a Norwegian forum it looks like. Seems a lot like someone who used to post here and did the same thing.

I suspect there are many people in Norway working at Porsche and BMW dealerships who just saw their sales fall to the floor over the last few months and are none too happy about Tesla.

 

[AmpedRealtor]

Thought I'll take a couple of selfies, of my foot:

- on the accelerator

- on the brake pedal

Hmm, I'm indeed dangerously close to slipping off the edge of the brake pedal with my size 11.5 shoes. Hasn't happened but, is likely if I'm not careful.

With all due respect, why are you putting your foot on the right side of the brake pedal while your foot hangs over? You have over 50% of the brake pedal available to the left of your foot that is being unused. This is clearly a photo of user error. Look at your foot. It's not even centered over the brake.

 

[tomas]

With all due respect, why are you putting your foot on the right side of the brake pedal while your foot hangs over? You have over 50% of the brake pedal available to the left of your foot that is being unused. This is clearly a photo of user error. Look at your foot. It's not even centered over the brake.

Amped, ignoring the hostile video of pump failure, I do not think anyone is suggesting that an incident of simultaneous brake/accelerator is anything but user error. What I think those of us who have experienced it are seeking is whether there is anything about pedal placement, brake pad behavior, hydraulics, etc. that make the user error more common in this car, so we can avoid or address. Doing some experiments tomorrow, should have some facts to post. There have been some very constructive suggestions made and I suspect there are some solutions.

 

[pbleic]

I think that many are missing the point that there are TWO directions in which the pedals can be separated. One is the horizontal distance - increasing this increases distance needed to travel to brake. Ok, possibly a safety issue. But the other is the height of the pedals. Most cars have an accelerator lower than the height of the brake. To go from brake to accelerator requires a sideways movement AND a drop towards the floor. That is the separation that Tesla can change.

 

[gg_got_a_tesla]

With all due respect, why are you putting your foot on the right side of the brake pedal while your foot hangs over? You have over 50% of the brake pedal available to the left of your foot that is being unused. This is clearly a photo of user error. Look at your foot. It's not even centered over the brake.

Right. Agree. It's just that the combo of my seating position (how much the seat's pushed back and how low it's at), my height (6' 1") and the placement of the pedals leaves very swivel room for the foot while pivoting on the heel. I'm taking FlasherZ's advice now and consciously trying to pick my foot up entirely to mash the brake pedal.

 

[woof]

Most cars have an accelerator lower than the height of the brake. To go from brake to accelerator requires a sideways movement AND a drop towards the floor. That is the separation that Tesla can change.

Just went out and checked my wife's S85. The brake pedal is about 1.5 inches higher than the accelerator (as measured from the bottom of the pedal to the floor mat on the "firewall" (or whatever it's called in an EV). From the 2nd picture angle you can see the brake is blocking the view of the accelerator as it is above it.

 

[dsm363]

Just went out and tried to do it. I just simply pick up the front of my foot and rotate it towards break and couldn't do it. I used two feet and pushed accelerator first then brake and car stopped. If your foot slips off the break and onto accelerator so not full pressure on break you will creep forward but get the alert. I simply don't see this as a problem but others do. Not sure what Tesla could do about this though.

 

[liuping]

I think that many are missing the point that there are TWO directions in which the pedals can be separated. One is the horizontal distance - increasing this increases distance needed to travel to brake. Ok, possibly a safety issue. But the other is the height of the pedals. Most cars have an accelerator lower than the height of the brake. To go from brake to accelerator requires a sideways movement AND a drop towards the floor. That is the separation that Tesla can change.

It's already more than an inch higher than the accelerator, are you saying it should be even higher?

 

[pbleic]

It's already more than an inch higher than the accelerator, are you saying it should be even higher?

I don't have my car yet. I was going on Nolands measurements in the original article this thread is about:

But more telling is the vertical distance between the surfaces of the Model S pedals--a scant 1.6 inches.

This turned out to be notably less than any of the 22 other cars I measured.

They ranged from a low of 1.8 inches (the M3 and CR-V) to 2.9 inches (Chrysler Town & Country minivan) The average was 2.2 inches--nearly 40 percent greater than the Model S's miniscule vertical separation.

 

[rlcordeiro]

Guys its not the height off the floor , it's the height in front of the gas pedal towards your face. When you push down on the brake the edge of your foot should not touch the gas pedal till the brake is fully activated.
@Liuping there are 25K cars between your vin and mine maybe Tesla already fixed the problem?

 

[pbleic]

Guys its not the height off the floor , it's the height in front of the gas pedal towards your face. When you push down on the brake the edge of your foot should not touch the gas pedal till the brake is fully activated.
@Liuping there are 25K cars between your vin and mine maybe Tesla already fixed the problem?

Good explanation. However, the difference in height off the floor between the two pedals and distance from your face is exactly the same. Height off the floor is easier to measure.

 

[tomas]

I did the research, measurements, and experiments, and here's my story:

FACTS:
* If you are actively braking, and then clip accelerator, there is NOT an accelerator cutoff, you get juice and braking at same time. If you accelerate first, then simultaneously brake, there is accelerator cutoff.
* The Model S is endowed with a tremendous amount of torque, which we all love. So, when you touch the accelerator, you get a quick response.

MEASUREMENTS:
* Difference in pedal depth (distance from floor or from driver) is approximately 1.5" in my car, consistent with Woof's measurement above.
* My pedal travel for a soft stop: ~ 1.5"
* My brake pedal travel for a hard stop: ~ 2"

EXPERIMENT:
* I do not have a 3D printer, as suggested by JRP3. But, I DO have duct tape and some high density foam packing. I cut a pedal sized 1/2" thick biscuit of foam, temporarily taped in place on pedal, and tested. I found that, in case of a hard stop, without the biscuit, I could easily clip the accelerator. With the biscuit, I did not. I got to the plane of the accelerator, but did not activate it.
* Without the biscuit, when I clipped the accelerator upon hard braking, I got the phenomena that the car just didn't finish braking, but also didn't accelerate. It just sort of kept gliding along at very low speed.
* Observation: the extra 1/2" did not feel un-natural or impede my driving in any way.

DEDUCTIONS REGARDING CONDITIONS UNDER WHICH THIS OCCURS:
* In my case, I did not make this driving error until my 15th month of ownership.
* I looked back through thread: Of the 13 posters who said they had experienced this issue, 11 of them have at least year-old cars (verified by signatures, or in some cases my prior correspondence with them on other issues). For the other two, I found no information. So, the reports predominately are coming from "older" cars.
* Though I have no way of testing my brake travel under soft and hard braking a year ago, I suspect that it has INCREASED. This is due to some combination of system getting spongier, and crud buildup (what SC incorrectly called "glazing") that never burns off due to the fact that most MS drivers accomplish 50% or more of their braking via regen, and seldom really exercise the brakes.
* I believe that this longer brake travel for hard stops has increased the probability of clipping the accelerator.

WHAT CAN I DO WITHOUT ANY ACTION FROM TESLA?
* I can try to retrain myself re: driving style. Especially in view of the low MS driver position, I find myself planting my heel between the two pedals and swiveling toe back and forth to select. This makes clipping more probable. I could work on my "lift and stomp".
* I can try higher ceramic content pads to try to minimize dust buildup and make brakes more "grabby", which should reduce brake travel - thanks Strider.
* I can fashion a permanent 1/2" thick brake pedal cover. Either find someone with 3d printer, or go prowl around home depot looking for materials.

WHAT COULD TESLA MOTORS DO?
* Offer a software selector between: HEEL & TOE MODE (no accelerator kill during braking, like now), and BRAKE ONLY MODE (accelerator inactive during braking).
* Install higher ceramic content pads, and shorten (currently 2 year) service interval and review criteria for brake flush.
* Move brake pedal 1/2" closer to driver.

 

[CanuckS#69]

* If you are actively braking, and then clip accelerator, there is NOT an accelerator cutoff, you get juice and braking at same time. If you accelerate first, then simultaneously brake, there is accelerator cutoff.

* I can fashion a permanent 1/2" thick brake pedal cover. Either find someone with 3d printer, or go prowl around home depot looking for materials.

This has been my observation as well. I have observed several occasions where I got a scary surge upon sudden braking without the two pedals warning, easily corrected by shifting foot position. FWIW, none happened until after about a year of ownership. I was a heel/toe manual driver before and have done track, autocross, etc. (Not a moron) I would think that the easiest solution is to change the firmware to always cut accelerator input when the brake is at all engaged, that being the safest behaviour. However, I also have to wonder whether the rubber pedals on production cars could be fitted to the Sig (Perf?) cars in order to change the pedal height slightly. I do *not* consider this to be a safety issue, but rather a driver error problem that can be improved upon.

 

[jbruce]

Yeah, no kidding. They've probably also never had to left foot brake to get an early AWD turbo car on boost and appropriately balanced on corner exit. I've had to mod pedals in cars to make the brake and the gas closer for heal / toe. This guy David Nolan needs wear some better driving shoes and master the pedals.

Something tells me the writer of that article never was a fan of heel toe shifting :tongue:

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Chris Harris on left foot braking from his Autocar days https://www.youtube.com/watch?v=vcSAiRxmm0w