While driving in autopilot the car will randomly slam on the breaks multiple times at all speeds from 30-60mph even when the road is empty. This can increase if a large bus/truck is on the other side of the road in the opposite direction.
2021 Tesla Model Y driver assistance complaints
Page 16 of 22: complaints 431 to 460 of 630, newest first, as owners wrote them.
On almost all my long highway trips (about 4 hours long), if I have traffic aware cruise control (TACC) enabled on my Tesla Model Y, I experience one or more episodes of phantom braking. The first time it occurred I had owned the car for only a few weeks and was not yet accustomed to its fast acceleration. I was driving at about 70mph on a clear day with no one in front of me when the car suddenly braked. My first impulse was to hit the brake to disengage TACC, but I realized that would slow down the car more, increasing the chance I might be rear-ended. So I hit the accelerator and rocketed back up to 80mph before settling back to normal speeds. I was fortunate to be on a straightaway with no one ahead of me. Since then I have experienced phantom braking with TACC enabled under similar circumstances, i.e., with no cars or trucks in front of me and in clear weather in daytime. With more experience, I have noticed that the problem happens more often when I am passing a truck on the highway, especially when doing so around a curve. In past years I have driven numerous rental cars with adaptive cruise control and have never experienced anything like the phantom braking of the Model Y. This is not normal behavior and I hope you can get Tesla to fix it.
Phantom breaking while driving with cruise control.
On 2021 August 18 Wednesday at approximately 2:40 pm (Eastern time USA) and again at 2:59 pm, my Model Y braked severely while driving at high speed. Weather: Moderate to heavy rain due to passage of the remnants of Hurricane Fred. Location - incident 1 (about 2:40 pm): Pennsylvania Turnpike eastbound, just west of the Somerset exit. Location - incident 2 (2:59 pm): PA 219 South (limited-access expressway) near Meyersdale, PA. Situation/speed - incident 1: (2:40 pm): Driving in the passing lane traveling at approximately 70 mph. Cruise control was engaged. Situation/speed - incident 2: (2:59 pm): Driving in the passing lane traveling at approximately 70 mph. Cruise control was engaged. Description of incident (2:40 pm): The incident happened on a downhill curve while passing another vehicle when the Model Y braked suddenly and sharply. The speed dropped from approximately 70 mph to approximately 40 mph. The area was a construction zone but not an active construction zone at the time. There were construction barrels and flags on the shoulder of the left lane. There were concrete Jersey barriers/K-rails in the median strip between the eastbound and westbound lanes. The lane markings were visible but may have become obscured by rain/mist and a vehicle in the right lane. There was no vehicle behind the Model Y. Description of incident 2 (2:59 pm): While passing another vehicle the Model Y braked suddenly and sharply. The speed dropped from approximately 70 mph to approximately 55 mph. The area was a staging area for a construction zone but not an active construction zone at the time. There were construction barrels and flags on the shoulder of the left lane but no other barriers or fences. The lane markings were visible but may have become obscured by rain/mist and a vehicle in the right lane. There was no vehicle behind the Model Y.
The vehicle sometimes brakes dangerously hard at highway speeds, nearly causing the vehicle behind me to nearly rear-end me.
This car is subject to frequent "phantom braking" . Using adaptive cruise control or full self driving, the car will occasionally brake hard for no logical reason. This happens every time I drive the car on two lane roads, i.e., with vehicles approaching from the opposite direction in the opposite lane. It happened from the time I took delivery until the present. It happened today (2-17-22). In 90% of cases, the phantom braking is triggered by a large vehicle - semi truck or bus, approaching from the opposite direction. In 10% of cases, the cause is either not clear, or caused by a smaller vehicle. The phantom braking occurs in all lighting conditions - right sunlight, overcase, night. The vehicle has not yet been inspected by Tesla.
I too have had an issue were without warning or provocation when on cruise control, whenever a semi-truck approached in the oncoming lane, or on four-lane divided highways, my car decelerated from 75 miles per hour to 40 miles per hour in a matter of seconds. I have also had the car phantom break when going under a overpass on a highway and while crossing 2 lane bridges. Luckily no accidents so far but definitely terrifying.
While driving at highway speeds I have recently had repeated unexpected breaking events occur while using adaptive cruise control. It happens without warning and for no apparent reason. The breaking is significant and could easily result in a rear end collision.
Our Tesla started last month braking suddenly and hard when cruise control was enabled. This is happening at night when cars are passing us going in the opposite direction. At no point did the braking occur due to cars actually being in our lane or potential accident. These braking errors happen when normal driving conditions under or at the speed limit with clear visibility.
I have had issues since i purchased this vehicle in march of 2021 where driving down the highway with Adaptive Cruise Control enabled and it will suddenly slam on the brakes at highway speeds with no other vehicles around. This sudden braking is so severe at times that everyone in the car is thrown forward and bracing for a false impact. This has caused several close calls for vehicles following me. Also the severity of the braking in winter weather causes the vehicle to lose traction and potentially place all the occupants and others on the road at risk. During my time in the FSD Beta program i was able to report all of these events, sometimes dozens of times a day. Eventually I asked to be removed from the program as it seemed worse in the program than when on a standard build version of the software.
The contact owns a 2021 Tesla Model Y. The contact stated while driving at highway speeds with the cruise control activated, the vehicle had erroneously applied the brakes causing the vehicle to reduce the speed. The failure had occurred on multiple occasions. The cause of the failure was not yet determined. The local dealer and manufacturer were not notified of the failure. The failure mileage was 10,000.
My Tesla Y suddenly decelerates while in cruise control at the same location on a highway. It occurs when I am passing an exit ramp, but not exiting. The car reads the exit ramp speed of 45 and suddenly decelerates from. 65 to 45. It never reads exit ramp speed when I am not using cruise control and am exiting.
Phantom braking at all speeds both on city streets and on highways. On the highway 138 between Palmdale and Victorville California I was unable to use cruise control because the car would continually brake. I was the only car on the road at the time.
When the traffic aware of cruise control or auto pilot is engaged, particularly on two-lane roads with opposing traffic, phantom breaking occurs with about 90% of the approaching semi tractor trailers, and perhaps 25% of the approaching automobiles.
While driving on C-470 in Colorado, eastbound approaching the Quebec St. exit, I was in the right lane. A car was exiting the highway while I continued straight. I was 2 sec behind this car and the car was in the exit lane, while I continued on the right lane. However, the highway curves to the left here. A straight forward view shows this car mostly in front of me. The Model Y braked excessively, from 65 to 45-50 before I could press the accelerator to continue forward. I would be worried of a rear end collision if there were a car behind me.
I've been having problems with phantom braking, primarily on highways. This problem has gotten much worse in the last month or two. The car will unexpectedly brake while either autosteer or adaptive cruise control are engaged while driving on the freeway, and typically (although not exclusively) when my speed is approx. 70-80 MPH (where speed limit is 75-80 MPH). This will happen approx. once every half hour, although it is sporadic and often happens in spurts. Until about 1 month ago this would happen only while autosteer was engaged. However, during the last month or so ago this has also been happening while adaptive cruise control is engaged (without autosteer engaged). It happens most often when I am in the left lane passing a semi-truck which is in the right lane, although it happens other times as well. Always without any warning. It has happened a total of probably 20-30 times in the last 2 months (approx. 5,000 miles). Sometimes it manifests as a gentle, almost tentative tap on the brakes, whereas other times it is a fairly jarring with sudden hard braking. It has not caused any accidents or incidents, but I am concerned about it happening when a car may be behind me. Because of that, I will often disengage cruise control or autosteer if other cars are close behind me. My car software is equipped with Full Self Driving, but the FSD (beta) has not been downloaded.
When driving with cruise control on I experience issues with sudden braking. Sometimes it seems like it may be an error due to on coming traffic (particularly trucks), but sometimes it’s due to blind curves or small humps (such as an interstate bridge/overpass) where the pavement is a different shade. Typically I’ll be at cruising speed 60-75mph and braking will be sudden and aggressive, to about 45mph. This has happened numerous times since purchase in June 2021.
The cruise control on my Model Y frequently slams on the brakes for no apparent reason (no obstacle or vehicle in my lane). This happens at all speeds (from 30mph to 75mph). The cruise control is so unsafe and scary that I will not use it at all with other passengers in my car or when I have a car following me. My car slams on the brakes so hard it makes it completely unsafe for me and the people following me. In my opinion, it drastically increases the chances of being involved in a rear-end collision. There is no ability in the Model Y to use cruise control that is not adaptive-based. Until this problem is fixed, Tesla needs to offer a cruise control option that is 100% controlled by the driver (standard cruise) where the speed and brakes cannot be changed by the car. My car has not been inspected by the manufacturer and this has not been reported to the manufacturer because it is a widespread and known problem, and Tesla is not currently doing anything to help others who have reported the issue.
The adaptive cruise control and lane assist on the Tesla Y models are defective and pose significant risk to drivers, occupants and surrounding traffic. Phantom braking and sudden slowing are common place and many times unpredictable. Countless times when oncoming traffic in the other lane approaches, sudden braking and aggressive slowing will occur especially if this happens to be a logging truck or larger vehicle. Coming under any overpass or bridge will also produce phantom braking. This will happen countless times in a single trip rendering the adaptive cruise useless. I complained to Tesla and was called by the corporate office in Denver and told that this is a reality and it was my responsibility to "teach the neuro-net" that it's phantom braking was an error by accelerating aggressively during those episodes and producing "bug reports" to Tesla! I have had this Tesla 3 months now and have stopped using the cruise control and lane assist because of safety concerns. My attempts at "teaching" the computer the correct response has utterly failed. I have had 3 episodes that I know of that someone following closely behind me had to take evasive action which precipitated "road rage" type behavior on their part for no fault of my own. Tesla has made no effort to correct this defect and have even cancelled my repair appointments stating it was"not needed". Every Tesla owner I discussed this issue with has a similar experience. Eventually someone will get injured or killed due to this defect.
The contact owns a 2021 Tesla Model Y. The contact stated while driving with the cruise control activated, the vehicle erroneously applied the brake. The contact stated that the brakes were immediately released independently of driver assistance. There were no warning lights illuminated. The failure had occurred approximately 6 - 10 times. The contact had not taken the vehicle to the dealer. The manufacturer was not made aware of the failure. The approximate failure mileage was 1,000.
When using basic Tesla Autopilot (AP) on side roads or highways the car will experience “phantom braking” with no other vehicles around. Phantom braking is where the car will slam on the brakes because it sees a safety issue ahead. I was driving on a highway at 60mph and engaged AP after about 5 miles the car brakes hard and fast down to around 40mph and then sped back up to 60mph after about 50 yards. It did this twice on the drive home. If we have an 18 wheeler behind us and they’re not paying attention they would definitely rear end our car.
The display of the rear view camera on the screen is not synched. Sometimes it shows something that happened moments earlier. For example, it may show me as I am walking toward the car. Then it “lags” as you back up, meaning that it shows you in an earlier position than where you really are. This is super dangerous as it may not show the real time presence of another car, a pedestrian who is crossing behind your car as you back up, or an object. It also give the driver the false sense of being in the wrong place. We have two Teslas, this is a model Y and the other is a model 3. We have experienced the same problem in both since Tesla pushed a software update in January. I notified Tesla and asked for a repair. The response was that a software patch would be forthcoming. That was weeks ago. Again, this is a super dangerous flaw in the software for the display of the back up camera. I am worried that a pedestrian will get run over by a Tesla driver who does not “see” that pedestrian in the back up screen, or a crash.
Two phantom braking incidents on loop 202 Wednesday night
Car rapidly brakes when in cruise control and auto pilot. Will also rapidly brake when a car passes by. It will always be random and sudden. Also, occasionally the screen will turn off and I will lose the screen completely and not know my speed.
Phantom braking, rapid deceleration occur without warning and randomly.
with cruise control on, when large vehicles (in their respective lane), would approach in opposite direction, the car would brake. Sometimes lightly, once (tour bus approaching) at 60 mph, the brakes were slammed on, with the car behind us nearly rear ending us
Hello, my Tesla Model Y frequently brakes unexpectedly causing me concern in traffic I could be rear-ended. This happens when engaged in FSD Beta software version 10.9 currently and has happened in all previous versions of the software as well. I have held a commercial drivers licnese and want everyone on the road to be safe as possible. The car brakes hard reducing speed 15mph in a second. The car has also attempted to take off from a red light when the first car at an intersection treating it as a stop sign when when several lights are present indicating a solid red and the screen in car shows me solid red as well. I have had to intervene many times to prevent accidents.
In 16 months I have experience 2 episodes of dramatic emergency braking while traveling at highway speed in the carpool lane adjacent to a concrete barrier wall estimated 5 feet high on the left side of the vehicle. The car decelerated from 65 mph to roughly 30 mph in roughly 2 to 2.5 seconds. Had someone been following at an unsafe distance an accident would have occurred. Thankfully it did not. I never experienced this in my previous Tesla Model S. Overall I love the vehicle, but these 2 incidents were disconcerting.
North bound on interstate highway, my vehicle rapidly deaccelerated and then accelerated without warning
The vehicle engages automatic emergency braking frequently and repeatedly without reason, especially on two lane highways with oncoming traffic. This occurs during the day and at night. The vehicle also engages phantom braking (without emergency braking notifications) during normal driving on freeways and highways. Video of this incident is also available.
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