2021 TESLA MODEL Y Forward Collision Avoidance Automatic Emergency Braking Problems

When driving with cruise control engaged the car randomly brakes and shows a "curvature assist " indication. The car quickly slows from 55 to 35 with no warning. This primary happens on a straight road, not a curve. I am concerned about the traffic behind me.

On October 2, my Model Y battery was replaced with a defective cell. Tesla service center replaced the battery. The vehicle could not charge or operate, making it unable to be driven. Today, November 2, while driving my car, my Tesla ABS system and other battery components experienced total failure while driving. For a brief period of time, I was unable to brake completely and my vehicle felt like it was skidding. At the time this occurred, my 1 year old daughter and pregnant wife were in the vehicle. This could have been much worse.

I was driving along one of the main highways in Orlando, Florida called [XXX], on Wednesday [XXX], in my Model Y Tesla. I was between the exits of [XXX], and [XXX]. I was in the middle lane. There was a software update issued the previous Sunday. The warning came on the display that the lane changing was not valid. At that point the car took over and accelerated. The brakes would not work, until I slammed on it after 3 times, and the car began to decelerate. The air conditioner went off, along with the electrical turn signals. I as able to get off at the [XXX] exit for it is a bit of a "hill" up in Florida, but knew I could coast into a lane hopefully no one would be in. I was able to at least coast into a parking lot, and bump the car into a...

Immediately after an over-the-air (OTA) update on Aug 8, 2025, my vehicle began showing camera connection errors and disabled multiple safety/ADAS features. Over the following days, I repeatedly received alerts that AEB was unavailable. The vehicle remained drivable, but AEB and related safety functions were inactive. Chronology: Aug 8, 2025: OTA software update to 2025.26.6 completed. Right after completion, the touchscreen displayed camera connection errors and disabled AEB / Autopilot / cruise control. Aug 11, 2025: While driving, I again received an “AEB unavailable” alert. Similar alerts appeared intermittently throughout the week. There was no water intrusion, impact, or external damage. Cameras were clean and unobstructed. I scheduled the earliest available Tesla Service appointment and reported the AEB failure as a safety issue. Service diagnosis: Tesla diagnosed a failure of the Autopilot computer (HW3) and ordered a replacement. Cost/coverage: I requested that the repair be covered by Tesla because the...

I WAS DRIVING ON AN INTESTATE HWY I-70 EAST BOUND ON THE LEFT LANE AND I WAS ABOUT TO TAKE THE EXIST 62. I WAS ON CRUISE CONTROL AND IT WAS RAINING AND THE ROAD WAS WET. WHEN I TRIED TO CHANGE THE LANE THE CAR AUTO BRAKED AND CAR SKID AND ROTATED 360 DEGREES AND HIT THE RAILING. THE CAR GOT DAMAGED FRONT AND BACK. LUCKILY THERE WAS NO VEHICLE NEAR US SO MY FAMILY WAS SAFE. BUT I DONT KNOW WHY THE CAR AUTO BRAKED AND ONE SHOULD NOT HARD BRAKE WHEN THE ROAD IS WET. I CALLED 911 AND TESLA INSURANCE. I TOOK THE CAR TO THE BODY SHOP AND THEY ARE DEEMING IT TOTAL LOSS. PLEASE TAKE NECESSARY ACTIONS SO IT DOESNOT HAPPEN AGAIN

While reversing in this 2021 Tesla Model Y (software v12, 2025.14.1, Full Self-Driving Supervised), the vehicle’s ultrasonic sensors showed a wall directly behind on the display. However, the Tesla Vision camera system did not visually render the wall, and neither Automatic Emergency Braking (AEB) nor Obstacle-Aware Acceleration activated. The car reversed under driver input directly into the wall, causing a collision with property damage. The safety defect appears to be that the ultrasonic sensors, although still present and visually displayed, are no longer integrated into the collision avoidance systems after Tesla’s software updates activating Tesla Vision. As a result, the AEB and OAA systems seem to rely only on camera data, ignoring ultrasonic sensor input — leaving a dangerous blind spot in reverse. This problem affects safety because the driver receives no warning that AEB or OAA will not engage based on ultrasonic detection alone. Tesla’s updated owner manuals (2023.12)...

Summoned my car in parking lot. Vehicle showed on app that it planned to go straight then turn left but instead cut to a left and thus colliding with the car that was parked next to me. I have the footage if needed. Car should have stopped instead, or followed planned route. I was staring at the car the whole time and it looked that it was going straight, even after colliding, it looked like it was aimed to go forward. The car created a log of what happened if needed.

My Tesla still has the phantom braking problem. It is repeatable and consistent. I can tell when it will occur on a route that I drive regularly. Day or night does not seem to alter the occurrence. There is no indication on the touch screen when this occurs. Traffic volume does not matter. It always occurs at the same places so it should be relatively easy to fix if someone would just monitor my computer when it occurs. I regard this as a dangerous problem on the freeway because my car suddenly slows and if the person behind me is not paying attention, I am going to be rear ended. Such a serious fault for a vehicle that performs so well otherwise. Since Tesla does not have a service center in my town no one has offered to look at the problem but since it has been reported so often,...

The issue appears to be an acceleration malfunction and brake failure in my 2021 Tesla Model Y. The vehicle is available for inspection upon request. On [XXX] at [XXX], while waiting for the garage door to open, the car experienced an unknown unintended acceleration malfunction, surging forward uncontrollably. It didn't wait for the garage to open, crashed through the garage into the family room, causing significant structural damage to the framing and door. The City of Eastvale declared the house unsafe, sealing it off. I am now homeless and staying with friends temporarily. During the crash, the airbags did not deploy, and the ABS system failed, preventing an emergency stop. The car stopped 4-5 feet away from my wife, who was on the sofa, posing a critical life-threatening situation. Thankfully, [XXX] and I survived, but this incident caused severe mental trauma for my family. We have not reported the incident...

Driving [XXX] enroute to Houston from Peoria, AZ, on cruise control, the auto braking activated aka ghost braking, causing the car to extremely brake. No other cars or trucks near us and no signs in area that might affect cruise control. I thought this was fixed! Totally unsafe. Luckily no one was behind us. This happened a lot back in mid 2021 and to have it still happen is hazardous. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

The vehicle's primary Autopilot processor randomly and completely failed while in active use on February 10th, causing the vehicle to immediately change course towards a highway barrier at high speed. Since that moment, every time the Autopilot DAS computer is reset, the primary processor refuses to transition from the INIT state to the NOMINAL state and instead transitions to CRITICAL state. The vehicle had software update 2023.44.30.8 for recall campaign #23V-838, recall number SB-23-00-008 applied 1 month ago, which was supposed to decrease the probable misuse of the DAS system. However, many individuals reported that the recall immediately and irreversibly damaged their DAS computer, so Tesla offered them a free replacement without hassle. However, I have been struggling to work with Tesla's Carlsbad, California service center for over a week to get the DAS computer replaced at no cost, since the computer was damaged after an update caused the computer...

I was driving to work this morning, February 7th, 2024 driving at freeway speeds. My Tesla touchscreen dropped out and went completely dark. The reset process is to press and hold for about 30 seconds and another 30 seconds for the full restart. I attempted this twice and proceeded to pull off the highway. During this period, I could not see how fast I was driving, whether my brake lights, turn signals, or headlights worked at this time to safely transit through traffic to get off the road. I put my hazard lights on, but again did not know if these worked or not. The screen finally came back online and seemed fine until I could get to work, this was an extremely scary experience and a perfect example as to why all cars should have a cluster driver screen mandatory, I will be getting rid of this car as...

Tesla Autopilot lost control in rainy weather, swerved off the road on freeway at 80mph, swung back in the leftmost lane and then to shoulder, risking lives of driver and all passengers including 2 children. Impact resulted in broken wheel rims and bursted tires. This could have been fatal accident if there are other cars on the road at the time of incident. There were absolutely no warning on the screen and near zero time to react with vehicle wheels turning sharp left at 80mph. Footage though immediately visible on DashCam has disappeared from USB drive. Requested vehicle logs from Tesla but that too has gap in coverage exactly during time of accident. Tesla Service Center has not responded to request to get system log at the time of accident. Missing logs and camera footage exactly at the time of incident is suspiciously missing. Footage and logs are available for...

While driving on highways using adaptive cruise control, the vehicle will slow down quickly from highway speeds of 60 to 75 mph, down to 40 or 45 mph without the presence of an obstruction in front, such as a vehicle, or even a shadow, that could fool the vehicle’s camera. This puts us at risk of being rear-ended on the highway. The problem happens randomly. I have reported the issue to Tesla twice. It happened once while on the phone with a Tesla representative that had called me back regarding my reported complaint. The Tesla rep said they were aware of the issue and were working on correcting the issue via a software issue. Tesla has cancelled my requests for service appointments regarding this issue. In September of 2023 we attempted to use the cruise control to see if it had been repaired but it happened again. There were no...

The Regenerative brakes malfunctioned looks like and the car kept on spinning and we hit the side of the freeway and ended up in a ditch and the tow truck had to pull us out of the rubble. it was very scary and lucky we did not get hurt. I was reading some online reviews and looks like many people are having similar issues with Tesla Model Y and other Tesla Models. thanks

Phantom braking. We were going at around 45 miles per hour on route 30 and the car suddenly engaged brakes without anybody in front of me. Apparently it's a known issue called phantom braking and I wanted to report it

What component or system failed or malfunctioned, and is it available for inspection upon request? Emergency Breaking in Autodrive mode. How was your safety or the safety of others put at risk? My car auto breaked hard for no apparent reason when I was driving at 75 MPH on an open highway. Has the problem been reproduced or confirmed by a dealer or independent service center? There are plenty of articles online about Phantom Breaking. Has the vehicle or component been inspected by the manufacturer, police, insurance representatives or others? No, this happened yesterday morning on 11/18/2023. I plan to report this to Tesla today as well. Were there any warning lamps, messages or other symptoms of the problem prior to the failure, and when did they first appear? Not a single warning and this was the first time that this has happened to my vehicle. I was driving using...

driving from Albuquerque NM to Farmington NM, in approximately 1 1/2 hours of driving on hwy 550, 4 lane divided highway, encountered no less than 12 hard shadow breaking events. in all instances there were no vehicles, animals or debris in front of the vehicle. It was a cloudless day, starting around 9am, clear no fog, temperature in the 40's. high risk of being hit if a car was following close behind, incident has been reported to tesla, no inspection. there was no waring prior to all hard shadow breaking events.

When travelling with adaptive speed control enabled the car will suddenly and violently decelerate 30 to 50 MPH below the set speed. This happens frequently and does not appear to correlate with anything specific. Sometimes it happens when passing a large white truck. Sometimes there is no other traffic anywhere near me. At the very least I would like Tesla to give me the option of disabling the "safety" features so the car operates like every other car with adaptive cruse control. This is not just me. Search the internet for Tesla phantom braking and you will find many instances going back years. It seems to be getting worse with each software update.

During raining multiple teslas including my tesla last week experienced hydroplaning lead to close ti fatal accidents I believe the car inappropriately used emergency breaking that lead to accident, i am not if that was due to the car seeing water/reflection ln the ground I was driving the speed limit and all cars were driving at the same speed 70-75 mile per hour) I suddenly started spinning with no warnings It is impossible that multiple teslas experienced the same thing more than other cars I am trying to get the data from tesla to confirm this, but it is not easy to make them get us what exactly happened I am seeking third party analysis hopefully once i get the data, but it would be best done from NHTSA The damage to my car was due to hitting the road and my car went to the middle due to hight...

Dear Tesla Customer Support, I hope this email finds you well. I am writing to express my extreme concern and disappointment regarding a serious malfunction I experienced with my Tesla vehicle, Model Y, on 08/01/2023. The incident has left me deeply troubled and has raised significant questions about the safety and reliability of your vehicles. On the aforementioned date, while I was driving my Model Y, I noticed an unusual burning smell coming from the vehicle. Shortly after, the cruise control system began to malfunction erratically, leading to a loss of control over the vehicle's speed. In a matter of seconds, the display and all lights on the dashboard went dark, leaving me unable to monitor crucial information such as speed, battery level, and vehicle warnings. Worse yet, the electronic power steering suddenly failed, causing an immediate stiffening of the steering wheel and making it incredibly difficult to control the...

Approximately 11:26 am on Thursday July 27, and approximately 110 miles east of Gallup, New Mexico, I experienced when driving a 2021 Tesla Model Y, a series of extreme phantom braking events. One phantom braking event resulted in an extreme braking and the car gave a loud alarm signal. This happened while passing two rather closely spaced semi-trailer trucks that were in the right lane of the interstate highway 40 roadway going westbound. Both trucks were traveling without making any unusual movements. They were steadily traveling between 70 and 80 mph. There was a large SUV following our vehicle. This event resulted in an extremely hazardous condition. A high-speed rear-end collision was imminent. I, as the driver of the Model Y, immediately accelerated and steered over to the left-lane shoulder. No collision occurred and I was able to pass the two trucks and return to the right lane. Clearly, this...

Computer will suddenly error out and cruise control, AEB, forward collision warnings, and lane keep assist are not available. A warning "cruise control unavailable" shows if you attempt to engage autopilot or FSD. No forward collision warnings, no auto slowing down. Not docked for close following. No visualizations made. Not resolved with soft or hard reboot. Sometimes will randomly will allow to re-engage, other times I have to park the car and let it go to sleep without charging or sentry mode for things to reset. I've driven many, multiple times including for 1.5-2hour segments with a frozen visualization and no AEB or cruise control or FSD. Speed independent, weather independent. Time of day independent.

My family and I were driving from San Diego to Arizona on Interstate 8. I was utilizing autopilot (adaptive cruise control with lane keeping assistance) and 4 different times the car slammed on the brakes from approximately 75 mph to 60 mph. We were driving on a bright, sunny, extremely hot day (116 degrees). Luckily there were no cars behind us or we could have been rear-ended. It's also noteworthy, there were no cars/vehicles in front of us or objects in the road when the phantom braking occurred. I now no longer feel safe using autopilot on our Model Y. No warning messages appeared and no additional information was provided by the car. We have used autopilot on several other road trips and never experienced this issue.

I was driving the speed limit with the adaptive cruise control engaged on I-95 in Maine with no one in front of to the sides of me. All of a sudden without warning my car brakes on the middle of the highway. I regained control right after and did not use the adaptive cruise control for the rest of the drive.

Phantom braking in autopilot. Traveling at 75mph with traffic behind, fortunately the car behind was not following closely. No warning message beforehand, just happened very suddenly with no obstructions in sight. Weather was clear and sunny, no traffic in front. Two minutes later, the car completely ignored a deer standing on the hard shoulder!

We have recently experienced a significant and concerning increase in incidents of phantom braking and have thus far been unable to receive an adequate response from Tesla. We have had at least six instances of this occurring today, 16-Jun-2023 in the first 6-7 hours of our cross-country drive, and I’ve shared these time stamps with Tesla service. This is because we experienced this same thing 2-3 times on another long drive in November of 2022, and Tesla service told us at the time they couldn’t do anything about it unless we had time stamps because otherwise, it’s too many pages of code to sort through and beyond that, you have to notify them within 12 days of the incident or they can’t look into it at all (which is what happened with me- although I had to chase them to even get a response). They also said it was a...

Countless times, at high legal speed, with adaptive cruise control enabled, on a straight blemish-free level highway with perfect visibility, sudden automatic deceleration was experienced-- several times every hour over 11 hours of driving. I have video recordings.

Repeated "phantom braking" caused by shadows from clouds, pavement coloration changes, billboards some distance from the highway, large advisory signs, and even pieces of blown-out truck tires on the shoulder produce sudden deceleration of over 30 mph in just seconds from the automatic emergency braking system on my 2021 Model Y Performance. This mostly occurs on interstate highways or secondary highways when the vehicle is in cruise control or auto steer with cruise control mode. A recent trip of several thousand miles produced over 20 cases of phantom braking. The windshield area in front of my forward facing cameras is always kept clean. HAZARD: It has created the risk of rear-end collisions, or stimulated road rage from following drivers.

For last several months my 2021 Tesla Y is experiencing phantom braking while using cruise control. Happens about once every 50 miles on the highway and occurs on straight roads with no traffic in front or behind and no road hazards. Braking is sudden and hard and represents a significant hazard . Thanks

On a trip from Spokane to Seattle on 5/27/2023, while traveling at 72mph on I-90, we experienced “phantom braking”. This resulted in the vehicle rapidly decelerating based on its detection of something in front of the car to avoid a collision. This occurred 3 times on the trip, and in no case was there anything for the vehicle to avoid. Weather was clear and road conditions were dry. Our biggest concern is that there could have been someone following directly behind, and would have certainly caused an accident if this were the case. The Tesla was in “autopilot”, which is the only mode we have experienced this. We experienced this last year on the same stretch of I-90, just east of Moses Lake to just west of George Washington.

The contact owns a 2021 Tesla Model Y. The contact stated while driving 55-65 MPH, the vehicle experienced "Phantom Braking". The vehicle was not diagnosed or repaired by an independent mechanic or the dealer. The manufacturer was not made aware of the failure. The failure mileage was approximately 22,000.

I own a 2021 Tesla Model Y. I took possession of it on August 7, 2021, in Santa Barbara, Ca. Ever since, I have had thousands of instances of automatic emergency braking (phantom braking) episodes while using cruise control or autopilot. On January 26, 2022, I had 47 documented episodes, in just two hours. The experiences of severe phantom braking have been terrifying. The car often slams on its brakes for no apparent reason, many times on a four lane highway, or on a freeway with no cars or obstacles. I worry about getting rear-ended, which could end in severe injury or death. It has been in for repair five times, and the technicians are animate that a software update is coming very soon to resolve this problem (they've been promising that since a few weeks after taking possession of the Tesla). I expected the problem to be resolved by...

On the evening of April 18, 2023, I was driving on the southbound 101 in Northern California using autopilot, and despite the surrounding area being clear of other vehicles, pedestrians or debris, without warning, the autopilot system forced the vehicle to suddenly and harshly brake. It was completely unwarranted and unexpected and really gave me and my passenger a scare, and this ain’t the first time it occurred. We purchased our vehicle in November 2022 and in December we were using autopilot on the 405 south in Los Angeles, traffic was moving at a steady 70MPH when the vehicle abruptly braked, thinking it was a one-off we didn’t report it but after reviewing several complaints of similar issues by other Tesla owners, this is a real problem. I saved the event on my Tesla dashcam.

Severe phantom braking incident - 12:18 CST, March 12th 2023, followed by less severe braking problem at 1:16, 1:23, 2:18 on the same day and road. No forward traffic, no hazards, just bright sun. The car with a less experienced driver applied hard braking nearly causing a rear end collision with a truck approaching from the the back. The truck moved into the shoulder and passed to avoid hitting the car.

The contact owns a 2021 Tesla Model Y. The contact stated while driving approximately 75 MPH with the "auto pilot" and the "cruise control" functions engaged, the vehicle made an emergency stop. The contact stated that the force of the emergency braking had thrown him forward into the seat belt. The contact stated no warning light was illuminated. The contact was able to disengage the auto pilot and cruise control and continued his trip. The contact stated that the emergency or "phantom braking" had become a recurring failure. The contact scheduled a remote service for the vehicle and an over-the-air software update had been performed. The vehicle had been repaired. The contact stated that the failure continued after the software update. The manufacturer had been informed of the failure. The failure mileage was approximately 18,000.

Vehicle began showing the below warning messages, followed by loss of power steering and abnormal braking behavior (brakes did not work properly). This is a recurrence of an issue that previously resulted in the vehicle being towed to Tesla, but whom were unable to diagnose the problem. -Automatic Emergency braking disabled -Lane Departure Avoidance features unavailable -Traction control disabled -Automatic vehicle hold disabled -Stability control disabled -Steering assist reduced -Front motor disabled -Power reduced

This is my second NHTSA report for this car, there was no reply to my first report. Since the manufacturer, without warning or owner consent, disabled radar systems for automated cruise control, the car is now exhibiting a new dangerous behavior when the camera detects the presence of emergency vehicle flashing lights and suddenly, and dangerously applies an emergency brake to slow the car, without taking into consideration the location of the emergency flashing lights relative to my car, or the presence of other cars around me that might be affected by the sudden, un-announced braking of my car. In many cases, the police/emergency lights are on the opposite side and direction of the freeway, 8+ lanes away from my car, and I am under no legal obligation to brake, nor would it be safe to do so. There is no warning by the car, only the sudden braking action...

This car is unsafe. 70K+ purchase price with the inability to use basic cruise control, must-less the 10K FSD purchase that is USELESS. The phantom braking is constant while trying to use the basic cruise control, auto-pilot/FSD. Driving this car makes me a nervous wreck and I am beginning to HATE it and regret my purchase. I am seriously concerned for the safety of myself and other Tesla owners based on the current radar-less autonomous features. NHTSA should get involved and force Tesla to address the phantom braking issues before more people are involved in an accident that could be avoided.

The contact owns a 2021 Tesla Model Y. The contact stated that while entering or exiting the driveway on an incline, the automatic braking system engaged and locked up the tires in icy conditions. While reversing, the contact noticed that he was unable to turn off the integrated braking feature. While driving the brake pedal was depressed but the vehicle failed to brake efficiently. There were no warning lights illuminated. The local dealer was not contacted. The vehicle was not diagnosed or repaired. The manufacturer was not contacted. The approximate failure mileage was 1,500.

There are multiple issues: 1. When trying to back up slowly, or move forward slowly, the car goes automatically on park "to prevent roll". I am intentionally trying to slowly back out of parking, and the car keeps stopping 2. When I try to change lanes, in many cases the car gives a solid "beep" which is equivalent to me almost crashing to another car. But there are no other cars! 3. The car keeps giving forward collision warnings when there is no immediate danger to collide with anything, and in most cases there is nothin in front.

The contact owns a 2021Tesla Model Y. The contact stated while driving 65 MPH with the cruise control activated, the vehicle independently and aggressively slowed without driver input. The vehicle then accelerated independently. There was no warning light illuminated. The failure occurred approximately 10 times. The vehicle had not been taken to the dealer to be diagnosed or repaired. The manufacturer was not made aware of the failure. The approximate failure mileage was 65,000.

It seems like this is a common problem if you search "tesla phantom braking," which very obviously needs a solution. I commonly experience the phantom braking when there is a shadow like passing under a bridge. The car will slam on the brakes thinking the shadow is another car, which is obviously extremely dangerous especially on the highway. A simple solution would be to add a legacy cruise control option, while fixing the phantom braking. This would cause a lot less wrecks and deaths.

On February 19, 2023, I was driving my 2021 Tesla Model Y on I-5 from LA to Sacramento on a clear afternoon. I was using adaptive cruise control (ACC) set at 78 mph, but not using auto-pilot, in the fast lane with a car following me. My car suddenly braked aggressively without anything in the roadway ahead of me. I then applied the foot brake and veered off onto the gravel left shoulder to avoid having the car behind me hit me. I saw in the rear-view mirror the following car swerve to the right to get around me, entering the slow lane. I believe that when I stepped on the brake, the ACC turned off and the car's automatic braking ceased. I then got back into the fast lane as there were no other cars approaching and resumed my drive. I didn't notice the speed my car had decreased...

I have been driving long distance 418 miles today from Phoenix, AZ through Las Vegas, NV and north. In my 6 hour journey today my breaks were applied randomly by the computer around 20 or more times on autopilot and on cruise control. It is an extreme safety hazard. I want this on record because this is day one of a cross country trip and in case anything happens. The phantom breaking was so frequent in the last hour I could not drive with autopilot on anymore for fear of a car following me would crash into me at highway speeds above 65mph.

Numerous times we have experienced phantom braking when the cruise control is engaged at highway speeds. We think it occurs when you are close to cresting a hill and a vehicle is detected in the distance. The vehicle is quite distant, perhaps 500-1000 ft, but the auto braking system only see a short distance of lane lines (because they are out of sight on the other side of the crest) and interprets the vehicle to be much closer. This generally occurs about once every 100 miles of highway driving. Because of this, we are reluctant to use the cruise control. The date provided below is just the latest occurrence.

Experienced phantom braking twice today on I 5. Almost crashed or got rear ended. Car was on auto pilot. This needs to be fixed

While driving on the highway at 70mph, on two separate occasions while using autopilot and cruise control, the car suddenly braked for no apparent reason. There were no vehicles immediately behind me at the time, however this was terrifying because I was scared that I was going to be rear ended at a high speed. I can no longer trust this safety system due it has happened twice randomly now.

SYSTEM MALFUNCTION: Emergency braking ("phantom braking") while set to automated driving/adaptive cruise control. OUR SAFETY PUT AT RISK: On a 2,000 mi. road trip from Denver CO to Tucson, AZ and back, the vehicle slammed on the brakes at 75-80 mph speeds over two dozen times. All incidents occurred either driving south on I-25 or west on I-10 going to Tucson, or on I-10 east and I-25 north on our return. By far the most dangerous event occurred when we were driving east on I-10 in SE Arizona on our return to Denver on 29 January. Driving in the right lane at 75 mph on a perfectly clear day with excellent road conditions, the vehicle suddenly slammed on its brakes. Following closely behind us was a semi-tractor-trailer, that also slammed on its brakes, blasted its horn, and very nearly rear-ended us. The truck driver then followed us at very close...

The car brakes at highway speed with no safety hazards in sight. This phantom braking occurs while on cruise control or when using the accelerator pedal. We don't use auto pilot. It is very upsetting and could cause a rear-ending accident.