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Autopilot disengages to reverse causing accident

Autopilot disengages to reverse causing accident

I got into an accident today because I was not used to autopilot. I usually drive a model 3, but this time I was driving a model X. I had autopilot on and wanted to change lanes on a congested freeway and turned on the signal stalk. The car started to slow down to find a spot and I decided to take over since it was taking so long so I instinctively flip the right stalk up as I do in my model 3. What happened was that this put the car into reverse. Not realizing this and upon seeing space up in front of my vehicle, I pressed the gas pedal which caused my X to move backwards, rear-ending the vehicle behind me. At first I thought it was all my mistake, that I probably pushed the brake pedal or that I'm too used to 3 to cancel autopilot with the right stalk.

I then recreated this scenario in a less congested area. I turned on autopilot and followed a car to a red light which slowed down both of us to 5 mph. Then I flipped the right stalk up to cancel autopilot and it indeed put the car into reverse. At higher speeds when I tested around 30 mph, flipping the stalk up to cancel autopilot put the car into drive.

Well, the accident occurred and my insurance premiums will go up as well as I have to shell out money to repair my trunk door. I also sent an email to Tesla and will see what their response is. I'm sure this is not the first time this has happened and it should be fixed with a firmware update. No driver would go from autopilot to reverse. It's the last thing on my mind when I am driving on a freeway trying to merge. Hopefully Tesla can fix this problem and I guess I'm also giving a PSA. I feel like there were several design flaws in this scenario that if fixed, could've prevented this from occurring.

nukequazar | 23. September 2019

On S/X all of the AP functions are on the dedicated AP stalk on the left. Having AP controls on different stalks on the two different models is poor UX but having an AP command share the same control motion as putting a car into reverse could be deadly. Hopefully this will change. This story seemed so weird I searched online and found a video about Model 3 AP controls that shows these functions. The driver even remarks, "it's a little unnerving to push up on the stalk to cancel AP but it's never gone into reverse for me."

lilbean | 23. September 2019

You can also cancel autopilot by turning the wheel.

EVRider | 23. September 2019

I’m having a little trouble believing this story. First, when using auto lane change, the car doesn’t slow down to find a spot in the next lane. Second, you can only shift from drive to reverse if you’re stopped or moving less than 5mph, but you said you were moving forward trying to change lanes. I don’t doubt that someone could accidentally shift into reverse, but it seems unlikely in the scenario you described.

hiltxan | 23. September 2019

Using auto lane change does slow down if the lane I was in was open and the lane on the right was congested. It was in fact what prompted me to take the autopilot off because I would’ve missed the exit if the autopilot took too long.

Regardless, you can try autopilot and let the car slow down to 5 mph and then hit the stalk up on an x or a s. For me the car went into reverse. Tesla should have kept the stalks consistent on the 3 and the x/s and maybe should not let drivers disengage from autopilot directly to reverse when hitting the stalk up at low speeds.

nukequazar | 23. September 2019

AP will definitely slow down to make a lane change. This is an area that will hopefully improve. The car sometimes slows very abruptly which feels dangerous and rude to drivers following.

hiltxan | 23. September 2019

Also, I’m not sure that people should rely on turning autopilot off with brakes or turning the steering wheel since it disrupts the car from normal moving motion. I believe the stalk method to be the safest and smoothest. Why cause stress for the driver behind you when you tap the break or swerve the car a little and bother the passenger to disengage autopilot.

nukequazar | 23. September 2019

@lilbean, turning the wheel will cancel steering and lane change control but not speed control. Only hitting the brake or cancelling with a stalk will fully cancel AP.

jrweiss98020 | 23. September 2019

I have to barely touch the brake pedal to disengage the AP on my Model 3. I haven't tried yet, but I bet I could do it with my left foot and barely slow at all...

andy.connor.e | 23. September 2019

Im having trouble with the part where OP switched to reverse while moving forward in autopilot, and then pushed the accelerator and it reversed the car that was apparently moving forward.

rxlawdude | 23. September 2019

If you're moving at speed, hitting the gearshift lever into the "R" position will put the car in Neutral. At slow speeds, it's possible to go from moving forward to being in reverse.

That said, all of this is resolved by the OP's very first sentence: "I got into an accident today because I was not used to autopilot."

Don't use autopilot if you're not familiar with it.

tigerkc | 23. September 2019

Model S will not switch to reverse if you are moving forward at more than a few miles per hour. I have tried that on my model S.

So the issue is simply OP has mistaken the control on the X versus the 3.

andy.connor.e | 23. September 2019

+10 @rxlawdude

hiltxan | 23. September 2019

Correct, autopilot will not go into reverse if you are driving at higher speeds. I tested it at 30 mph and it just disengaged autopilot and did not allow me to go into reverse. Once the car slows down to 5 mph, try hitting the right stalk up and you will see the car goes into reverse. Your car can still move forward slowly even though the “gear” is in reverse.

I think I am used to autopilot, as I have used it for thousands of miles on the 3. It was when I switched to the x to drive did I get confused. So then it must mean I am used to autopilot on the 3, but not the x. In any case, I still think it’s a bug that needs to be fixed or Tesla should’ve kept the same stalk on the left for the 3 but it’s too late now.

Sad thing is I had to explain to the couple I hit that I was confused by autopilot. Their first words were that I should not be using autopilot on the freeway in congested areas and they are probably never going to buy a Tesla after this incident which is a shame. I didn’t have time to explain the nuances of autopilot but I still enjoy driving Tesla’s and will continue owning in the future.

andy.connor.e | 23. September 2019

that is not a bug. Its a learning curve between different Tesla models.

hiltxan | 23. September 2019

It’s not a bug that at 30mph it disengages autopilot and at 5 mph it goes into reverse?

Do you or anyone drive both a 3 and an s/x? This would only happen to a very small subset of people who drive both designs.

andy.connor.e | 23. September 2019

It sounds like you hit the stalk that you thought was the AP stalk and instead you switched the car into reverse. If you try switching the car into reverse at 30mph, it does not change transmission but it disengages AP. If you try switching into reverse at 5mph it switches to reverse.

Im not sure what you are asking.

hiltxan | 23. September 2019

Shouldn’t the stalk disengage autopilot into drive or neutral no matter what speed it disengaged at so there’s is a consistency? Having a cutoff of 5 mph (not sure if it is, but I was able to go into reverse at 5 mph) to go into reverse just seems dangerous. Autopilot can function at 5 mph as well when traffic slows down or merging as what happened to me.

andy.connor.e | 23. September 2019

This sounds like a learning curve.

hiltxan | 23. September 2019

I guess I should learn how to drive an x then. But a good design would also prevent user error like this.

andy.connor.e | 23. September 2019

agreed. and im sorry, but so would reading the manual.

mbirnie51 | 23. September 2019

Don't use autopilot if you're not familiar with it.

That's a Catch 22: You can never get FAMILIAR with something unless you USE it.

That being said, it is the users responsibility to inform ones self with AP. If the different models have stalks in different locations, the user must be very diligent with it's operation.

I feel sorry for hiltxan, but its mostly on him.

I'm now going to go out and see if I can get my MX to go into REVERSE while simulating his conditions. Hope it can be done in a parking lot!!

hiltxan | 23. September 2019

Parking lot may not work since autopilot cannot engage due to lack of lines. But I was also able to go from adaptive cruise control to reverse at slow speeds around 5 mph (I had to deliberately line my car up behind a parked car to slow my car down)

Let me know if anyone is able to recreate this scenario with autopilot.

EVRider | 23. September 2019

@hiltxan: Okay, I believe you now.

All Tesla models will let you shift from drive to reverse if you're going slower than 5mph. The difference is that the Model S/X don't use the gearshift for AP control, but if you shift into neutral that should disengage AP.

As I discovered today when going through a car wash, it's very challenging to shift a Model 3 into neutral. You have to push the gearshift up (or down if coming from reverse) and hold it for more than one second before it will go to neutral. This is necessary since you also push up the gearshift to cancel Autosteer. In the S and X, you can just push the gearshift up (or down) to shift into neutral, since there's a separate stalk for Autopilot.

hiltxan | 23. September 2019

It's just interesting to think about since I work in healthcare and we have what we call a "swiss cheese model" in analyzing errors. This would apply to anyone in engineering or aviation and other fields as well. There were multiple times this error could have been prevented but it just so happened that it all aligned together to cause an accident. I treat it as a case study to learn from.

1. Driver has to be used to driving a 3 and then switching to an X/S. (Could have been prevented with same configuration on the 3 and the X/S)
2. Engaging autopilot and have a need to disengage at low speeds.
3. Hitting the gearshift stalk up to cancel (out of instinct due to the model 3) on the X.
4. Car not disengaging autopilot into neutral at slow speeds (Tesla firmware should be consistent in having autopilot disengage to neutral or drive no matter what speed, definitely not reverse).
5. Of course user error and not understanding how to correctly cancel autopilot.

Most people who only drive the 3 or the S/X without having to switch between the two models will probably never encounter this scenario to begin with and can't possibly imagine how easy it is to forget which model you are driving when you're in a fast-thinking situation such as merging on a freeway.

PrescottRichard | 23. September 2019

I feel for you, what got you there was that you assumed the two models operated the same (both being Tesla cars).

Just like how I used to misspell words because I didn’t look them up because I thought I knew how to spell them. Except misspelling words didn’t get me in a minor car collision.

hiltxan | 23. September 2019

Happened to this guy too except he was driving the model 3 and it also disengaged to reverse but never got in an accident. Also happened when he disengaged autopilot at slow speeds by hitting the stalk upwards. He was luckier that he didn't get in an accident.

"On my way home from work tonight there was a lot of traffic from an accident. There was a lot of stop and go traffic. I was using NOA, but disengaged so that I could get closer to the vehicle in front of me. Somehow out of nowhere the car feels as if it slammed on the brakes. I immediately noticed that the backup camera was on and then I looked and saw that I put my car into "R"! I was going slow when I disengaged NOA (3-5 mph), but had to have been applying some pressure on the accelerator thinking I was going to move forward (I don't use creep). Once I noticed what happened I let off the accelerator immediately so I wouldn't backup into anyone (thankfully!)"

https://teslaownersonline.com/threads/d-to-r-shifting-potential-damage.1...

So then what is the correct way to disengage autopilot regardless of model? Always tap on the brake to be safest? Use the stalk but then risk car going into reverse at slow speeds? Why even teach or have an option to disengage with the same stalk as the gearshift stalk such as in the model 3?

SnoR | 23. September 2019

I don't know why Tesla had to get all minimalist. It's confusing in its own right, let alone between models.

EVRider | 23. September 2019

Keeping a separate Autopilot stalk (and dedicated wiper controls) wouldn’t have made the Model 3 any less minimalist, and would have made a lot of owners happier, especially those coming from other Tesla models.

PrescottRichard | 23. September 2019

I’m guessing you can’t push the stalk forward to dis-engage on the 3 then... Right?

nukequazar | 23. September 2019

Test. Not able to post a longer comment here, although posted to another thread just now.

nukequazar | 23. September 2019

I wouldn’t call this a bug, I would call it bad UX/UI (user experience, use interface) but in this case it’s not like having an awkward key command in a software app slowing your workflow, it’s a bad design that could injure someone.

nukequazar | 23. September 2019

I’m surprised that Tesla uses precisely the same motion on the same controller to cancel autopilot and to put the car into reverse. This is just terrible design and a safety risk. The problem is exacerbated by the fact that it is a slight variation of controller function between two very similar cars that the same person may drive, e.g. an S or X and a 3 in the same family, a 3 owner getting an S as a loaner, or a parking valet. In any of these situations, a reasonably experienced and knowledgeable person may make the mistake either their first time, while in a hurry, when tired, or in a stressful moment driving.

nukequazar | 23. September 2019

I think the root cause is that Tesla thought that they could minimize hardware controllers in the Model 3 compared to S/X and have almost all controls onscreen. Then they found that AP controls needed to have a hardware controller so they had to figure out ways to add AP functions onto existing hardware like the Drive Stalk and the Control Wheels.

nukequazar | 23. September 2019

The AP Stalk is probably the controller I touch the most in my Model S second to the steering wheel. Hopefully they will add a dedicated AP Controller to future Model 3's, and keep it in every car going forward.

NKYTA | 23. September 2019

@nuke “that it is a slight variation of controller function between two very similar cars that the same person may drive, e.g. an S or X and a 3 in the same family”

So you have all variants.

Color me surprised.

Give it up.

PrescottRichard | 23. September 2019

This reminds me of when I went from a 2013 P85 to my 2016 90D. The turn signal stalk and the AP stalk are switched. I did set cruise or AP by accident at times, but didn’t hit anyone / thing. Same thing happened when I went from my Prius to the P85... so I got to go through that twice!

andy.connor.e | 23. September 2019

I dont see why it shouldnt be universal among all their cars. A dedicated stalk for cruise control & AP would be good.

nukequazar | 23. September 2019

@NKYTA, what?!?

NKYTA | 23. September 2019

@nuke,

I drive A 2012 S, and a a 2018 3.

Stalks are different. Duh,

What, exactly is hard here, if you’ve RTFM?

nukequazar | 23. September 2019

Right but they both have AP stalks, which 3 does not. That’s the source of this problem, and I believe it’s a pretty serious design mistake.

But I know, I got it, because I say something critical of almighty Tesla, I must be a liar, jerk, paid troll, shill, never owned a Tesla, etc. I got it. I’ve heard it all before.

PrescottRichard | 23. September 2019

NKYTA knows what I’m talking about then. Turn signal and AP stalk are switched in those two.

NKYTA | 23. September 2019

And I don’t have TACC in my 2012. And no sensors or AP.

Read the Effingham manual for your car, or get of my street.

NKYTA | 23. September 2019

s/of/off/

nukequazar | 23. September 2019

Really, NKYTA, that’s your solution to a serious design flaw? Read the manual? Good luck with that. A well-designed consumer product doesn’t need a manual for its primary functions.

nukequazar | 23. September 2019

By the way, the OP knew how to use the car. They turned AP on, if you read the story. It was in the moment of stress in traffic that they reached for the familiar controller and caused the accident. This is the design flaw.

hiltxan | 23. September 2019

@NKYTA so if I'm understanding this correctly (I can't tell if you're sarcastic and I don't own an S), your model S is 2012 without autopilot or TACC so you do not have an autopilot stalk. If that's the case, you are preconditioned to the 3's layout and will never get it mixed up.

Simple minded people will just point fingers at the user and assign all blame. What a more analytical person would do is to figure out why the error occurred in the first place and if it's preventable.

Worst case scenario: Autopilot engaged on an X comes to traffic stop with a car in front and lots of pedestrians. Driver disengages autopilot by flipping stalk up since he needs to merge or make a turn and going into reverse unknowingly and car is still stopped. Light turns green, pedestrians still in rear, driver pushes gas pedal and crushes rear pedestrians. Rare - Yes, impossible - no, preventable - yes, harmful - yes.

Many devices and programs we use today have been "idiot-proofed". This is the goal of a good UX and many errors are prevented unknowingly to the user. For example, if a doctor prescribes a medication in the EMR which could cause an allergic reaction, the EMR pops up a message asking are you sure. When an error does occur, it does not hurt to have a discussion.

As for those people telling me to read a manual - I actually drove the X for several months and got used to the AP stalk on the left. I bought the 3 and immediately had trouble finding the stalk until I got used to the 3 stalk for several months. It was when I got back into the X that I was preconditioned to the 3 again and ended up having this accident.

andy.connor.e | 24. September 2019

You cant idiot proof idiots. They will find a way to break everything. You have to label hot coffee as CAUTION HOT because people who watch the water boil and pour the coffee and see the steam howling off the surface of the cup is not enough information to know its hot. You assumed it was the same and didnt check prior, thats on you. There is no design flaw here, because if you read about how to use your car before you use it then theres no problems. I used to drive a truck that had the transmission shift on the wheel, does that mean that i start to go and grab my windshield wiper stalk on my car for the transmission and claim design flaw? I suppose my muscle memory is probably used to a certain set of actions, but this is NOT a design flaw. The flaw is the user error, or rather, lack of desire to self-educate.

SamO | 24. September 2019

The fault, dear Brutus, is not in our stars, but in ourselves, for we are underlings."JC

SamO | 24. September 2019

The fault, dear Brutus, is not in our cars, but in ourselves, for we are underlings."

Mike83 | 24. September 2019

Some people should NOT have a driver's license.

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