It is uncertain which specific system/systems have failed/malfunctioned at this point. Despite frequent and consistent communication with Honda, no real attempt has been made to uncover the cause of this issue, and no solution has been provided. The vehicle has been, and is, available for inspection upon request. This is the 1st occurrence since the first event on 21 April 2025. This occurred on the interstate. During this event, the vehicle rapidly decelerated from 75 mph to 20 mph without the ability of the driver to intervene or take back control of the vehicle. This led to a very near miss as traffic was rapidly approaching the rear of my vehicle. At the time of the incident (5:10 pm), I was in the left lane. Traffic was moderate. The weather was clear and dry. CMBS was on. ACC was (status unknown). LKAS was on. RDM was on. Problem has not yet been reproduced but dealer has verbally indicated that they get frequent complaints about the system. This includes one employee who has experienced this on his personal vehicle. Many DTCs have been recovered from the vehicle’s log. Manufacturer: Yes, vehicle has spent 30 days, to date, in custody of Honda Police: Not yet. Will do immediately if advised Insurance Representatives: Not yet. Will do immediately if advised Others: No. Any work on the vehicle performed outside of Honda East Cincinnati will void the warranty No warning or alert (audible or visual) lights were present before, during, or after the event
2020 Honda Accord driver assistance complaints
Page 3 of 5: complaints 41 to 70 of 115, newest first, as owners wrote them.
On September 2, 2025 at 1004-1005 EST, my car phantom braked, when there was nothing in front of me and this time instead of just flashing brake on the dashboard, it actually breaks itself and threw me into the steering wheel thank God my seatbelt caught me, but it really choked me up. This has happened quite a number of times before, but this is the first time that it breaked when I actually stepped on the brake pedal it break itself myself also. The component is the automatic breaking for the collision impact that keeps phantom breaking on me. It has never been looked at by a dealer or anyone otherwise. The lamp that came on was the BREAK lamp where the rpm are at.
There has been multiple times that when I am driving on the highway doing 60 miles an hour, the dashboard will light up to BRAKE the car when there is nothing in front of the car, no other car no trash nothing. It has done this on slower roads where the speed limit is 40 mph and under but it will actually brake the car and I have had cars behind me when this happens. This keeps happening multiply times a week.
On July 30, 2025, my Honda’s Collision Mitigation Braking System (CMBS) randomly activated without any obstacles in front of the vehicle. Since then, this issue has happened numerous times while driving. When the incident occurs, the system flashes a “Brake” warning and suddenly applies the brakes while I am driving. This creates a serious risk of a rear-end collision, loss of control, or bodily harm. I had the vehicle inspected by an authorized Honda dealership on August 1, 2025 for this issue. Despite the inspection, the malfunction continues to occur. Although I have not yet been involved in an accident, this defect poses an ongoing safety hazard for myself, passengers, and others on the road. I request that the federal safety agency investigate this matter.
The Honda Collision Mitigation Braking System (CMBS) will randomly activate without any obstacles in front of the vehicle. Consequently, increasing the risk for car accidents, loss of control, and bodily harm. The car has not been inspected by a dealer or certified mechanic for this problem. However, the vehicle is available for inspection and repair as needed. While the incident occurs, the CMBS warning system will flash ‘Brake’.
When driving my car it will phantom break when there is nothing in front of it going down the highway 5060 miles an hour and it’s done at numerous times. I have not been in an accident yet, but it’s something that keeps occurring on my car.
To Whom It May Concern, I am writing to formally report a serious safety issue involving the automatic emergency braking (AEB) system on my Honda Accord 2020. The system has been engaging randomly and without cause, abruptly applying the brakes when there is no obstacle or hazard present. On multiple occasions, this malfunction has occurred while driving at normal speeds, including on highways and in moderate traffic. These sudden, unprovoked braking events have created extremely dangerous situations, nearly causing rear-end collisions and putting both myself and other drivers at risk. Despite there being no obstruction in front of the vehicle, the system behaves as though an emergency stop is necessary. This issue not only undermines the purpose of the safety feature but also significantly increases the risk of an accident due to unexpected deceleration. I urge Honda to thoroughly investigate this issue, as it appears to be a potentially widespread and dangerous defect. I am requesting that the company: •Address and correct the fault in my vehicle’s AEB system at no cost •Provide a clear explanation of the root cause •Inform me of any recalls or technical service bulletins (TSBs) related to this problem
During a forward-side lane departure collision in my 2020 Honda Accord, the Body Control Module (BCM), forward collision radar system, braking assist, and Vehicle Stability Assist (VSI) all failed to activate. As a result, the vehicle did not brake, warn, or stabilize before impact. The airbags also failed to deploy during the crash. My safety and the safety of others were put at serious risk, as the vehicle did not respond as designed despite being equipped with these systems. The car is now undrivable but available for inspection. This issue has not yet been confirmed by a dealer due to the car's condition, but similar failures have been reported in other 2020 Honda Accords already under recall. The insurance company did not request vehicle data and did not inspect the systems. There were no warning lamps, alerts, or messages prior to the failure; the malfunction occurred without notice. I am requesting that this vehicle be added to the existing recall list related to BCM and safety system failures.
Vehicle will randomly slam on brakes to a dead stop, engaging my seatbelt when engine braking behind a vehicle. Usually happens on surface streets when the vehicle in front of me is turning into a driveway/tight right turn. My velocity is decreasing & I am not at risk of colliding with the vehicle every time. System does not seem to register engine braking with a manual transmission as “braking.” I’ve nearly been rear ended several times due to coming to a dead stop in traffic. I’ve asked Honda how to permanently disable the system, with the only advice to turn it off manually every single time I start the vehicle.
The contact owns a 2020 Honda Accord. The contact stated that while operating the vehicle, the brakes had erroneously activated, causing the vehicle the suddenly decelerate. During the failure, the "BRAKE" light was flashing. The vehicle was taken to the local dealer who was unable to determine the cause of the failure. The contact was made aware of the federal safety agency Action Number: EA24002 (FORWARD COLLISION AVOIDANCE). The contact stated that the vehicle had experienced the failure listed in the investigation. Additionally, after starting the vehicle and driving forward or in reverse, there was a squeaking sound coming from the rear of the vehicle. The vehicle was taken to the local dealer who was unable to determine the cause of the failure, and informed the contact that the failure was a common issue, but the manufacturer had not issued a service campaign to address the issue. The failure mileage was 30,000.
False alarms (several hundred) with audio and visual warnings but no braking. ONE instance of false alarm WITH emergency braking from 55mph to under 30mph. I do not recall a false warning happening after sundown, ever. Alarms have occurred on bright days with sharp shadows, and overcast with no shadows. There always seems to be a solid overhead object being approached, overpass, railway trestle, solid bar supporting a traffic light. This is highly intermittent where alarms occurred 3 in a week, to 1 in a span of two months. The two constants I have noted are it happens during daylight hours and a substantial overhead object or structure is being approached. Alarms have been occurring since 2021 when i bought the car new off the lot.
- Component/System failure/malfunction: ADAS. Specifically, CMBS and/or ACC. - My car has repeatedly experienced unexpected braking events, rapidly bringing me to nearly a complete stop in the highway. During this time, I have no ability to control the speed of my vehicle. This has been occurring during my ~70 mile commute on I-675, I-75, and I-275. - Despite having the car on multiple occasions and for over a week collectively, the issue has not been replicated by the dealer. - The vehicle has not been inspected by the manufacturer, police, insurance representatives, or others to date. The Honda dealer has not initiated any further inspection. - During these failures, the car has (often) been braking without due reason or any alert to the driver. No system malfunction was found (either shown to driver or in computer log, as verified by dealer). Please review attached document for further details regarding the incident(s). This copy has been presented to Honda and the Ohio Attorney General.
The car brake by itself with no obstacles in the way
CMBS not working properly. The car automatically brakes without any collision risk even on a clear road with no traffic and clear weather. Have a huge risk of someone crashing the car from the rear due to immediate braking. This issue has appeared several times.
When I was attempting to merge into the turning lane the car slowed down by itself and abruptly stopped in the middle of both lanes while a car was behind me.
While I am driving I have experienced incidents where the (Automatic Brake System) AEB system engages unexpectedly, causing the car to brake hard without any obstruction or vehicle in front of me. This incident have happened on both highways and main roads. When my car unexpectedly breaks, sometimes I get a warning That Says Brake then the car Beeps and sometimes It won’t give a warning. Today when it happened it only braked once but like I said it happens unexpectedly. (2020 Honda Accord Sport 1.5lt)
The car's automatic emergency breaking activates randomly when there are no objects in front of it. This is very dangerous as the car is often driving full speed when this happens. I have found that this happens most often when I am driving under something, like an overpass.
All of the lights on my dashboard come on every few hours and go off. Vehicle is losing power as I drive. Multiple people with this make and model have expressed their concerns of the same issue.
My blinker won't appear on the dash. My trunk won't open. My back up camera won't come on at all. Can't adjust my exterior lights, stuck on the dimmest setting and can't change. Lights will also flicker and I have no control over it. My radio screen told me to enter a code but wouldn't allow me to. My break system light was on. There is warning reading adaptive cruise control see dealer, automatic emergency braking see dealer, lane departure warning see dealer. Doors locked and unlocked while driving. Air condition wasn't blowing the temperature it said, and acting as it was on low when it was on the highest setting. It is available for inspection upon request. I brought my car into a Honda dealership today. My car had to stay overnight because they were unable to address the problem. There were no prior problems or warnings beforehand. All these problems first appeared when I started my car for the first time on November 14, 2024. These put myself and others at risk because the doors locked and unlocked which could have caused us to get trapped in. The lights not working put me at risk at night because I could not see the road that good.
The 1st thing that happened was that all the components of ADAS stopped working in the spring of 2023. All the warning lights turned on in the middle of my commute home from work. It was very intimidating because I thought the car was going to stall in the middle of the highway, so pulled over to the side. I contacted Honda dealership and they were going to charge me to diagnose the problem. So I went to Autozone and it diagnosed my problem as "System too rich (Bank 1)". I went to an independent mechanic and they had the same warning on their machine as Autozone. They tried replacing an oxygen sensor, that did not work in getting rid of the problem with all my warning lights turning on. Again the ADAS component lights turned on and the system did not work. The next thing they did was replace 4 fuel injectors. I have not had any issues with my car since concerning this problem with fuel too rich.
Have taken my car to dealership 3 separate times for all warning lights illuminated. Last time they replaced the transmission for a CVT belt prematurely breaking and all codes went away for one day. Now all are present again. Emmisions system warning, lane departure warning, cruise control warning, exc. Every single light never goes out. Just spent 6k on a car that had under 100,000 miles because I was told it was the transmission belt only to come home and have the exact issues happen. The day it was taken to the shop, it stalled in the road and almost caused an accident on a major highway. At this point, I'm afraid to drive it.
The automatic emergency braking system malfunctioned on 7/18/24. I was driving approx. 20 mph on a local road and there was no vehicle, pedestrian, or other object in front of the car when unexpectedly the orange warning to brake came on and an instant later the car braked on its own and came to a complete stop in the middle of the road. Given the sudden and forceful stop, I went forward into the seat belt. Fortunately, there was not a vehicle behind me as I would have been rear ended putting both me and the people in the other vehicle in danger. I reported the incident to the dealer using their online system (I wanted to do it in writing, but could not find a direct email address), but have not heard back from them yet.
I was driving along the NJ Turnpike at approximately 65 miles an hour when the brake warning light started flickering on and off and then the brakes engaged. It was quick, as if I had stepped hard on the pedal. No vehicle was in front of me, but I was driving through the express EZ Pass lane. Later that same day, it happened again, but this time it was only as if someone tapped on the brakes. The brake light flashed then too. To answer the above questions: What component or system failed or malfunctioned, and is it available for inspection upon request? The Collision Mitigation Braking System, and yes it is How was your safety or the safety of others put at risk? Someone could have rear-ended me Has the problem been reproduced or confirmed by a dealer or independent service center? No Has the vehicle or component been inspected by the manufacturer, police, insurance representatives or others? No Were there any warning lamps, messages or other symptoms of the problem prior to the failure, and when did they first appear? The brake light warning flickered on before each instance
The collision mitigation braking system periodically activates when traveling on interstate highway when there is nothing in the roadway to cause this function to activate, causing the vehicle to stop suddenly then release which have caused potential rear-end accidents and possible injury to the driver r passenger due to the sudden stopping motion which propel the driver and passenger forward quickly without any warnings. Recently an warning error appeared to verify this malfunction. Which before 6/30 the warning error never appeared.
I was driving on a road that the car has been on hundreds of times. Flat, straight, dry road with no other cars around. The car all of a sudden braked very hard and the "BRAKE" light started flashing and beeping for about 3-4 seconds and then went off and then the brake fully released. It was like hitting an invisible wall and fighting to maintain control of the car at the same time. It came out of nowhere and was so shocking. There was nothing around me and no reason for the AEB system to be used. I can't tell you if my foot was pressing on the gas or had lifted to maintain speed. I do know that my foot was on or lifted above the gas pedal and nowhere near the brake. I am shocked it didn't cause an accident but I am guessing that is because I held tight to the steering wheel and possibly because there were no other cars around. I have severe whiplash, a major headache, backache and am very scared driving the car should it happen again. I have not gone to receive medical treatment yet but it is highly likely that I will need it. I will be contacting the dealership as well to discuss.
I've owned the car for over a year now, bought it for my daughter. 3 times the emergency braking system has gone off while driving for no reason. the last event happened while driving on a Hwy at 55 mph with no in front of her. The car slammed on the brakes, and the brake warning light went off, thankfully no one was behind her.
On [XXX] I took my elderly mother to physical therapy and the car began to randomly brake although there were no vehicles in front of me. The braking light flashed and then car brakes on its own. A week later I was driving approximately 55 mph on a major highway and the car started braking again but without the warning light. Again, there were no cars anywhere around me. The next day I went to the Honda dealership in Covington, LA because I am very concerned this will happen again unexpectedly when there are cars around me and it will result in a bad accident injuring myself or others. I was told he can keep my car all day but he said they probably could not recreate the issue so its just a waste of time. He said nothing he can do about it. That's just how it is and maybe it was from a bug passing the sensor. I know have to remember to turn off the feature every time I drive because I am terrified that it will randomly brake again and it may cause a serious accident. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)
Vehicle engaged emergency brake by itself. Also in regards to current fuel delivery recall, Honda has yet to fix my recall saying they have not come up with the parts yet. This is my only vehicle that I bough to commute to work of 150 miles a day. The car stalls on the highway becoming more often than not and is hard to start sometimes.
This car brakes while we are driving while there is nothing in front. was reported to the dealer, they can not find the issue unless the carb does it, or I can turn off the program, but that is not a safe move.
Open highway traveling 50+ mph, changing lanes from middle to right. Car's emergency brakes turned on and slowed me down abruptly for about 1 full second. Thankfully no on was behind me and no one was hurt. I have had this car for 6 months and this has happened 2 other times.
VIN decoder
See the problems and recalls for an exact car
Buying a used 2020 Honda Accord?
Check the exact car before you pay: accidents, salvage or flood titles, odometer readings and previous owners.
Check its history