The vehicle will unexpectedly slam on the brakes while using the Traffic Aware Cruise Control. I've noticed it happens mostly on two lane highways with oncoming traffic or heavy shadows on the road. It will also happen on interstates when a shadow is on the road or a dark patch. I'm afraid I will be rear ended if this continues.
2021 Tesla Model 3 driver assistance complaints
Page 14 of 16: complaints 371 to 400 of 431, newest first, as owners wrote them.
When using Autopilot and/or cruise control, the vehicle will brake hard for absolutely no reason. For example, when driving at highway speeds, the vehicle will drop from 70 mph to 45 mph in an instant. In my experience, it tends to happen when there are sudden changes in ambient light.
Phantom breaking has occurred regularly with this vehicle when using adaptive cruise control on two-lane roads. Oncoming traffic in the opposite lane will cause the vehicle to suddenly decelerate, which has led to moments where the vehicle was rear ended. This has most typically occurred during curves in the road. There has never been a valid reason for the sudden deceleration, and the car is apparently confusing the oncoming vehicle with a imminent danger.
During a 144 mile trip, my late 2021 Model 3 "phantom-braked" 4 separate times in just one day. Meaning the car saw some imaginary object in front of it and proceeded to slam on the brakes with traffic behind me. The first two occurrences this day were due to what I'm assuming is the shadow of two Semis. The third occurrence was after driving past a van on the shoulder with the autopilot system off. The last occurrence, before I seriously began to feel unsafe in this car, occurred when about to cross below an overpass with nonexistent traffic in front of me. Up until this specific day, I've experienced 4 phantom braking events spread across 4 months and 4500 miles. After today, and an additional 4 occurrences of phantom braking added within a few miles, my model 3 feels unsafe to me
Our 2021Tesla Model 3, delivered in September 2021, has ongoing, repeated problems with sudden, unexpected braking, whenever cruise control or auto-steer is engaged. This happens regularly while driving on two lane highways, usually when a large sized vehicle is approaching in the opposing lane, but it also occasionally happens when there is no oncoming vehicle. Typically, an alarm also sounds and a warning light flashes in the car, warning of imminent collision risk. This happens every time we have used cruise control or auto-steer sometimes with nearly every large oncoming vehicle. This is unsafe because of the risk of a rear-end collision. The car dramatically slows. It also risks injury to the car occupants from being thrown forward unexpectedly. Along with the alarm and flashing signal, the braking is so dangerous and unnerving that it makes cruise control and auto-steer unusable. We have complained to Tesla of this problem. Tesla recently shipped the car to inspect more fully at its facility in Honolulu, but so far has reported that it is operating within "normal parameters." The rep suggested that the cruise control is not designed to work on a two lane highway such as we have on the Big Island of HI, although she says that it does not happen with every Tesla here. It occurs even on straight, level sections of wide, two lane highways with clearly marked lanes and wide shoulders. Tesla still has our car. When we read the Washington Post article explaining that many others are experiencing this problem, we felt we should report as well. We have advised Tesla that the cruise control and auto-steer functions in our car are unsafe and unusable in their current condition. We do not use cruise control or auto-steer except to test whether the problem has been fixed. We do not have full self-driving.
While driving the vehicle using autopilot or adaptive cruise control, the vehicle "phantom brakes" - meaning the vehicle abruptly applies the brakes to slow down even though there are no obstacles in the road. This happens almost every time either one of these systems is used.
The vehicle, while operating in autopilot mode, will automatically brake aggressively for no apparent reason. No physical object including shadows or potholes are in the way for this to occur. I have experienced this phantom braking on multiple occasions while using the driver assist mode on (autopilot). Being the attentive driver that I am, I quickly disengage the autopilot and manually take over to avoid a rear end collision. I have not had the vehicle inspected by Tesla or my insurance company as this is apparently a common theme with this car.
When in Autopilot (Adaptive Cruise Control) the vehicle intermittently slams on the brakes at highway speeds. I have not been able to determine any pattern for when this will happen - it’s disruptive and potentially dangerous.
When adaptive cruise control is engaged the car brakes when it sees oncoming traffic even though the vehicle is clearly in it lane. This also happens when it sees a semi truck driving in the same direction but in the adjacent lane. Its at a minimum annoying but it is quite dangerous especially when cars are behind me.
The car was running 2021.40.6 at the time of latest incident, but have noticed it with previous verisons as well. Car abruptly brakes HARD on the freeway when autopilot is being used. I have the non-FSD beta version, with just basic autopilot. I had to immediately intervene to prevent a car behind me from colliding. The driver assumed i was brake checking them. I've seen reports of this incident repeat with other Teslas owned by friends - have not gone to the service center as they aren't very helpful with software issues. The car has not been inspected I don't recall receiving any warning from the car - the car suddenly started braking hard on the freeway, so i had to disengage autopilot and accelerate immediately
The problem I am having, when I use traffic-aware cruise control, is "phantom braking" This has occurred multiple times on two-lane highways when a large truck is passing in the opposite lane, and sometimes on a freeway when I pass a large truck that is in the right lane. The car suddenly slows or stops and the forward collision warning alarms sound. My vehicle is available for inspection upon request. This upsets everyone in the vehicle because it is so sudden that they are startled and frightened when the alarm sounds and the car abruptly brakes. My wife has asked me to not use the traffic-aware cruise control at all because of this problem. I have owned the car almost 9 months and my wife has not and will not drive it because of the this problem. It is also quite dangerous because a vehicle behind me would not be expecting me to slow down or stop when there is no apparent reason to do so and may crash into my car. I have not contacted Tesla because I have thought the problem would be fixed by now with a software update, but after a number of updates the problem persists. I know other Tesla owners are having the same problem. I will contact Tesla today.
Recently, at least it was noticed starting in Dec 2021, while driving on two lane highways under cruise control or self driving, the vehicle would brake hard at vehicles approaching in the opposite lane. Large trucks especially triggered the response. The braking response definitely put the safety of the occupants and following vehicles at risk. I have not taken it to a dealer or service center. There were no warning lamps, messages or any symptoms prior. I have stopped using those features while on two lane roads. I certainly am hoping for a software update to solve this issue.
When driving north on Highway 61 between St. Louis, MO and Hannibal, MO and using "autopilot" adaptive cruise control, the vehicle will slam on it's brakes even when nothing is on the road in front of it. It happens multiple times through the duration of this trip. It's absolutely terrifying, and I hope it doesn't ever take effect when vehicles are behind me. It's so scary that I've stopped using cruise control out of fear it will brake check for no reason and cause an accident.
Phantom braking when using cruise control. Car suddenly braking or rapidly decelerating for now discernible reason when traveling at speed on highways, both two-lane and multilane. The problem has occurred many times since first acquired in December 2021.
Emergency braking is applied while using adaptive cruise or autopilot. This happens on two lane undivided roads with larger vehicles approaching on the opposite side. It does not happen with cars or pick ups. For no reason the forward collision warning will sound and emergency braking is applied. If a vehicle is behind my car I would have been rear ended. I have sent error reports over the air to Tesla at the moment. I also brought my car into service and documented this issue. They did recalibrate the forward cameras but no difference was seen. Just out of the blue the car will.reduce speed by 20 mph. In my video the speed went from 46 to 29. The funny thing is it did not slow fir the oversized truck. I have videos if the incidents but I cannot upload them on here.
Since purchasing my Tesla new in 6/21, I've been experiencing random and dangerous "Phantom Braking" where the vehicle will suddenly brake hard on the highway for no reason. On a few occasions, this created a hazard for motorists behind me. This has been occurring in rural and urban settings with the vehicle's cruise control or AutoPilot set. It doesn't matter which system I use, phantom braking is persistent in both. I contacted Tesla service twice on this issue and each time I was informed "no malfunction found with sensors or vehicle operation." I was hopeful that Tesla would release a software update to mitigate this issue (other Tesla owners have voiced this issue on social media and forums), however nothing has been resolved in the 7 months I've owned this vehicle.
Hello, Driving on a snowy road around 20 MPH. Attempted to slow down in a straight line, used the brakes to try and slow vehicle to go into a driveway. Vehicle would not respond to any inputs. The brake pedal seemed frozen, coming off and back on the brake pedal did not change anything. There sounded like an ABS pulsing but it was not working. Post accident pictures showed it looked like the car was dragging one axle like it was locked in the snow. Car ending up grazing a mailbox post and afterword said 'take control'. I believe the car tried to do an automated braking maneuver which did not work. The road was covered in 1-2" of snow and the mailbox would have been a reference point in the distance. When turning the steering wheel away from the object that was hit, the car continued to go straight like the wheels were not attached. The car never veered left or right during this whole event even though i tried to turn.
Purchased my Model 3 in August 2021. Autopilot and cruise control features worked flawlessly for the first few months of ownership. In September of 2021 after a software update, the vehicle started to perform unsafe reactions while on autopilot or cruise control. If any large vehicle like a semi-truck or vans were traveling in the opposite direction of travel on any two lane road, cruise control or autopilot will slam on the breaks and activate the forward collision warning tones. Reactions like this from driver assist technology could easily result in a multi-car accident. While commuting on a busy road (10 miles) on cruise control/autopilot, this issue could occur over 10 times on one drive. While making contact with Tesla service in September, a representative said that Tesla's autopilot software team was aware of the issue affecting Model 3's similar to my VIN. The representative ensured that the team was working on a software update to fix this issue. This problem continued until January 13th when I had a service appointment where I stated the same issue. The technician wanted a ride to experience the issue the car had. After getting the issue to reoccur, the technician stated that "he had never seen this problem before." After he fixed an unrelated issue with the car, he reassured me that the issue is know by Tesla and they were working on a software update to resolve the issue. After over three months with this major safety defect, I am reporting this issue to the federal safety agency.
Dangerously brakes for no apparent reason while using adaptive cruise control. Especially common on two-lane roads. Occurs approximately once every 20 miles of driving. Has caused near accidents on three occasions. Tesla does not take any action. Car has the most recent software update.
On *multiple occasions* when driving on a highway and using cruise control, the car has suddenly and severly decelerated. Tesla advises that for my vehicle the safety system to detect possible collisions is still in the "BETA phase" and has initially been programmed to be over-sensitive. Tesla claims that as software updates are made, this issue will improve. [See uploaded screenshot of text chat I had with Tesla service on 1/19/21.] I have an appointmnet to take the vehicle in, but Tesla says I must be able to give then exact dates and times of occurrences or otherwise there is too much code on the vehicle's computer log for their systemt to be able to analyze. (I am able to give them some dates but not exact times.) My fear and concern in the meantime is that such unpredictable deceleration events when traveling at highway speeds could result in a rear-end collision with a vehicle behind me. When I expressed this to Tesla, their reply was: "It is the driver's responsibility to stay alert, drive safely, and be in control of the vehicle at all times." I pointed out to them the obvious fact that none of those things can prevent this issue from happening, and received no further reply.
Multiple phantom braking incidents on regular cruise control (not autopilot).
The car repeatedly applies the brakes when the cruise control is engaged when there is no imminent safety issue. It will do this on the highway when vehicles are following putting me at risk for a rear end collision. When I use the cruise on secondary roads (to stay under the speed limit) the behavior is similar. The car will apply brakes for passing shadows, again putting me at risk for a rear end collision. I no longer use the cruise function because the braking operation is unpredictable and it is, in my opinion, generally hazardous.
Multiple random automatic braking occurred during Freeway cruising
On 1/3/21, approximately 2pm. Driving south on I-77 in the city of Broadview Heights. In center lane of highway with Autopilot (speed and steering only) on. A Hummer in my left lane drifts into my lane and hits my car (I have video). No alarms or alerts went off to warn me. No automatic steering occurred. My car continued in lane and at speed (about 64mph), until my driver mirror broke off and adjusted my position to the left. Broadview Height police report # [XXX]. I have a service request into Tesla. I am awaiting the at-fault party insurance to contact me to begin repair process. To above questions: -I am suspicious about the ultrasonic sensors and/or camera and it failure to warn me I was about to be hit. -I was hit on my driver's side by a car that was not detected by my Tesla -I have a service request made to Tesla, awaiting response -No inspections or diagnostics have been performed yet by Tesla -No warning occurred. I am very familiar with the warning my car can produce: things like drifting out of my lane; someone in front of me braking hard; or Autopilot applying brakes when it thinks a car is in front of me (when it's actually on a curved road). INFORMATION Redacted PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6).
Several times during every drive where Cruise Control/Autopilot is used, an event known as "Phantom Braking" occurs often time triggering the collision warning systems with no danger present. Phantom breaking is the automatic braking of the Cruise Control/Autopilot systems when no danger is present, causing an unexpected and dangerous automatic braking event. I wish to emphasize that this happens when either system is used under safe conditions and even within the guidelines recommended by Tesla. It is available for inspection should it be necessary. During these events, a vehicle following mine can and has been caught off-guard by the sudden braking, resulting in near-miss rear-endings. The danger of a vehicle collision is extremely high in these scenarios. The problem happens consistently on two-lane roads with no median using standard cruise control (Autopilot is only recommended on divided highways/interstates). Phantom braking still occurs at random in varied environments with both systems. My vehicle has not been taken to a dealer, but the issue has been confirmed/acknowledged by the manufacturer with no solution. This vehicle is new and delivered to me this year. The problem has been occurring since taking ownership/lease. Aside from the the emergency collision warning chime occurring sometimes at the same time as the braking event, there are no symptoms, warnings, or lamps appearing prior to the automatic braking nor afterwards. I have attempted to use the vehicle's camera recalibration and have changed available safety settings to every combination possible to attempt a consumer fix for the issue, but no combination of settings seems to keep the automatic braking events from happening
Phantom braking events on most every type of road and drive when using cruise control, not autopilot or other automated systems. Standard cruise control is unusable and is a safety concern with constant warning alerts and automatic emergency braking when other vehicles pass by safely in the adjacent lane.
Constant “phantom braking” when using autopilot on the freeway and other roads. When the pavement changes color, the car slams on the brakes in the middle of the freeway. When a truck is in the opposing lane, the car slams on the brakes. When a truck is merging into a lane to my right on the freeway, the car slams on the brakes. This is extremely unsafe and frightening. This software is garbage and worse than my 6 year old Subaru. Tesla needs to address this, and I hope they’re eventually forced to.
We continue to have issues with Tesla's autopilot feature. The Model 3 with autopilot activated or just with the adaptive cruise control activated, will "phantom" brake for zero reason. Today, 12/14/2021, it happened three times within 90 minutes. All three times there was no reason for the car to make emergency actions. Once I had a truck with a trailer behind me, forcing them to brake hard to avoid hitting the rear of the car. I submitted a service request to Tesla and this is what they told me: Incidents like the one you are describing where the vehicle slowdowns for apparently no reason are generally caused by a few reason such as: Map data inaccuracy, Speed limit data inaccuracies, the vehicle reacting to an upcoming event, GPS position inaccuracies, and predicative driving anomalies. In all of these situations the computer is trying to make the safest determination of what to do with the information that it being fed. To us as drivers, it would seem like a bad decision, but the computer uses our input following these events to get better at predicting how it should respond. Anytime you intervene with an autopilot behavior decision you are helping the system as whole get better. There are no faults with any of the hardware in the vehicle and at this time these behaviors are a limitation of software in the system. Our engineering team is working to improve auto pilot with every firmware update and we hope to see improvements in future updates. I'm sorry you feel that was Justin. Future firmware updates will improve functionality. You always have the options of not using your AutoPilot until they do. Thank you
On a daily basis while using the Adaptive Cruise Control or Tesla Autopilot, I will experience multiple erroneous automatic braking events. The car generally slams the brakes on when it is cresting a hill, attempting to pass a semi truck, or when sun angles produce large shadows in the road. The automatic braking events are sometimes very aggressive and can be extremely dangerous, especially if someone is following behind you in high speed traffic. My wife has requested that I don’t use cruise control or autopilot while she’s in the car, as we experienced an unwarranted, aggressive automatic braking episode which caused great pressure against her pregnant belly on a previous road trip. Additionally, the cameras on my vehicle will often produce warning/error messages stating “X camera is blocked or blinded” for absolutely no reason other than headlights from oncoming traffic shining into my lane. I am unsure if this contributes to the automatic braking issue.
My Tesla Model 3 is brand new and delivered in 2021, the vehicle has had no recalls or issues report by the manufacture and is running the latest software updates provided by Tesla, which as of this date is: 2021.36.8 I have driven the car since delivery a total of 5,596 miles, which includes a cross country road trip from CA to FL. During this trip I used "Autopilot" a feature which is touted as safe, however after my experience and reading and hearing other users reports I believe this is not the case. I had numerous cases of "phantom braking" which is where the vehicle believes there is an object that it will collide with and it slams the brakes on, usually dropping around ~20 MPH extremely rapidly. Many of these events occurred in lower light scenarios (night time) and almost all of them occurred when I had no vehicles in any direction for over half a mile, which means that there should have been no indicators flagging an emergency braking event. Here are some other reports, including a well known publisher CNET: https://www.cnet.com/roadshow/reviews/2021-tesla-model-y-review/ The Model Y and 3 share a lot of common design and technical elements, including their lack of a forward radar system, which is think is likely why this issue is occurring for these vehicles and not for the Model S and X. Here is a full user report: https://www.youtube.com/watch?v=uxvh60zBl70&t=1s I am writing this report in order to add myself to a growing list of Tesla customers that have not been listened to about this issue, it is a massive safety issue and should likely trigger a full investigation, this issue can easily be replicated with and 2020-2021 Model 3 and/or Y. And likely should trigger an immediate call for either a software patch, disabling of the feature, and/or recall of all affected vehicles, either to retrofit a radar system, or to fix the camera system.
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