2020 Tesla Model X: adaptive cruise control problems

Filed Oct 6, 2026 · Driver assistance · TX

I own a 2020 Tesla Model X equipped with HW3 and Full Self-Driving (FSD). After a Tesla software/FSD update earlier in 2026, the vehicle began experiencing a recurring problem during FSD operation. The issue has now occurred more than 20 times. During certain FSD-controlled maneuvers, particularly when turning from a complete stop onto a higher-speed road, FSD commands unusually aggressive acceleration. During the acceleration, FSD abruptly aborts/disengages and the vehicle logs diagnostic fault code DI_w124. Cruise control and FSD then become unavailable. There is one particular location where the condition is highly reproducible. FSD turns from a stop onto a road with a 50 mph speed limit, rapidly accelerates the vehicle, then triggers DI_w124 and aborts. Tesla previously inspected the vehicle for this issue and advised that the vehicle hardware checked out normally. The problem has nevertheless continued through subsequent Tesla software updates. After another recent software update, I tested the same maneuver again on [XXX], and the same DI_w124/FSD abort occurred. The problem did not occur prior to the earlier software/FSD update and appears to be associated with FSD-controlled acceleration rather than a general vehicle hardware failure. I am concerned that a driver-assistance system commanding aggressive acceleration and then unexpectedly disabling itself during the maneuver presents a potential safety risk, particularly when entering a 50 mph roadway or merging into traffic. Tesla has previously inspected the hardware but the condition remains unresolved. I am reporting this so the federal safety agency can determine whether other 2019–2020 Tesla Model S/X HW3 vehicles are experiencing the same DI_w124 fault during FSD-controlled acceleration. here is a link to the video that was taken a few months ago. [XXX] INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

Filed Jan 23, 2024 · Brakes, Driver assistance · AZ

On [XXX] at [XXX] my 2020 Tesla Model X Long Range Plus suddenly started braking while on the highway. I was driving 75MPH to San Diego from Arizona. There was no vehicles around or in front while using the cruise control. This also has been an issue with our 2023 Tesla Model Y and previous Model 3 while driving to Las Vegas at 70MPH. I really think this is safety concern. Luckily there was vehicles behind us with all incidents that took place. I recently took the 2020 Tesla Model X on [XXX] for the issue and the technician found no issues while driving it. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

Filed Jun 10, 2023 · Driver assistance · CO

I have driven this vehicle approximately 28,000 miles. I am the original (and only) owner. When using the cruise control the car will break suddenly and aggressively for no apparent reason on the open road. This has happened more than a dozen times. I cannot say what percentage of my driving is done with adaptive cruise control functioning but I would suspect well less than 30% of the 28K miles. On several occasions I surmise it my be related to oncoming vehicles in their normal lane. Fortunately, these episodes have not resulted in any collisions to date.

Filed May 28, 2023 · Acceleration, Brakes · NC

repeatedly, i have had my car brake harshly when travelling anywhere from 30-55 mph while using adaptive cruise control. there is nevere anything in the road or a car anywhere nearby to warrant a dramatic braking. the decelertion is harsh and alomst caused someone behind me to hit me on 2 occasions. i have repeatedly told Tesla about this and mostly gotten a nebulous response about "hardware" or 'software" issues and that they are working on it. This is dangerous and hurts when it unexpectedly happens!!

Filed Jun 3, 2022 · Driver assistance · NJ

When using any driver assistance function (autopilot, adaptive cruise control, or autopilot with navigation), phantom breaking is common and terrifying. I am scared to use the systems now because of how unpredictable phantom breaking can be and how jarring (and unsafe it could be) when it happens.

Filed Mar 18, 2022 · Acceleration, Driver assistance · IL

1) Cruise control randomly resets itself to different speeds. Happens several times daily. I can set it to 55 and 5 seconds later it will reset itself to 80 and accelerate suddenly, or vice-versa. It can change to any speed-either higher or lower than what I've set. Happened yesterday afternoon (3-17). First noted it being a problem 2-28 at about 6 pm MST while driving on 4 lane highway in Colorado, with multiple episodes of randomly resetting speeds itself. Given the rapid acceleration/deceleration of a Tesla, when the cruise control resets itself, the acceleration/braking can be abrupt and significant. 2)Ghost braking has been and remains a problem with this car. It was serviced by Tesla 2-18 and a "chip" was replaced per Tesla. I reported about a dozen incidents of ghost braking to Tesla shortly after picking it up but don't have exact times/days. There are 3 episodes of ghost braking that were truly dangerous. I was driving on the Interstate at 70-75 mph and the car slammed on the brakes for no reason, and it seemed it would have stopped completely in the middle of the Interstate if I hadn't accelerated manually. Speed went from 75 to 50 within 1-2 seconds before I was able to react and accelerate. Twice this happened at about 1-2 am on a completely empty interstate in Nebraska with no one around me at all, but the 3rd time was on a busy highway (I-55) near Chicago. I was nearly rear-ended by another car when this braking occurred. He was able to swerve around me, but was unhappy and made his displeasure known. Even if it didn't directly cause an accident it certainly triggered road rage, which is probably more dangerous than actually having an accident these days. Have told Tesla about it before but they always tell me it's just "software" and will get better with updates I have notified Tesla of these incidents (with written record) but haven't heard back from them. I have a service appointment 3-21-22 to get them to try and address these issues

Filed Mar 2, 2022 · Driver assistance, Electrical · 10,000 miles · CO

The contact owns 2020 Tesla Model X. The contact stated while using the self-driving feature or the cruise control, the vehicle would brake independently. The contact stated an unknown warning light was illuminated. The contact stated he had experienced the failure on multiple occasion. The contact called the local dealer and made them aware of the failure. The vehicle was not repaired. The manufacturer had been informed of the failure by the App. The failure mileage was approximately 10,000. The VIN was not available.

Filed Feb 18, 2022 · Brakes · VA

While cruise control is activated, the car brakes aggressively for no reason. This has happened multiple times in the last few months. I saw that news articles mention model 3, y and s but this is a model X and it is happening on this model as well.

Filed Feb 17, 2022 · Driver assistance · CA

Vehicle randomly breaks hard when either in cruise control or auto pilot. Either on normal highway lanes or in the diamond lane. Happens frequently - at least weekly on local Southern California Hwys

Filed Feb 3, 2022 · Driver assistance, Electrical · 46,000 miles · IA

The contact owns a 2020 Tesla Model X. The contact stated that while driving at various speeds with the cruise control or autopilot functions activated, the brakes inadvertently engaged, causing the vehicle to come to an abrupt stop. The vehicle experienced phantom braking. The contact stated that after the full self-driving beta program was installed, the failure occurred. The vehicle was taken to the dealer. The dealer transferred the contact to the tech department. The tech department informed the contact that they would repair the failure with an over-the-air software update. The vehicle was not repaired. The manufacturer was made aware of the failure. The failure mileage was approximately 46,000.The contact owns a 2020 Tesla Model X. The contact stated that while driving at various speeds with the cruise control or autopilot functions activated, the brakes inadvertently engaged, causing the vehicle to come to an abrupt stop. The vehicle experienced phantom braking. The contact stated that after the full self-driving beta program was installed, the failure occurred. The vehicle was taken to the dealer. The dealer transferred the contact to the tech department. The tech department informed the contact that they would repair the failure with an over-the-air software update. The vehicle was not repaired. The manufacturer was made aware of the failure. The failure mileage was approximately 46,000.

Filed Feb 3, 2022 · Driver assistance · CA

While on autopilot or cruise control, the car would suddenly and abruptly slam on the brakes for no reason. There's no traffic or objects to avoid. It was very startling because it could have caused a massive rear-end collision had I not intervened to cancel the autopilot and speed up again. . Because of this, I have stopped using the autopilot feature altogether. I cannot trust it will work properly. I have mentioned it to Tesla and they simply say the software update will solve it. It has not!

Filed Jul 18, 2020 · Electrical · 3,100 miles · CA

The instrument cluster does not show a valid speed. Speed is shown as '0' even when vehicles is traveling and even when cruise control or 'auto pilot' is driving.