Which parts fail
Components named in complaints (automatic emergency braking, adaptive cruise, lane keeping, backup camera).
Mileage when the problem started
Owner reports
Selected complaints filed with NHTSA by 2021 Nissan Altima owners, lightly cleaned up (personal details are redacted by NHTSA).
While driving home from work I experienced my fourth or fifth malfunction error flashing across my digital display. It scares me because this time is different. This time the flash made the seat vibrate and before I had a chance to react, I totally lost control Of my steering even though I had my hand family placed on each side of the wheel none of my maneuvers resulting in the tires moving in any direction. I was trying to straighten myself out but the trajectory Steered me to the right side of the road and up over the curb which tore out my front end And, had it not been for my superb braking skills, id be headfirst into a big cement hole on the side of the road. Brakes We're locked out until I pressed on them 15,000 times it seems. Fortunately I am the only one hurt, I'm grateful that no one else has been involved in this malfunction of supposed quality machinery. …
The contact owns a 2021 Nissan Altima. The contact stated that while driving approximately 25 MPH in a rainstorm, the automatic emergency braking system warning light illuminated, however, the vehicle failed to stop. The contact continued to drive and noticed that once they cleared the rainstorm the warning light disengaged. The contact informed the dealer and was informed that the repair was not covered under warranty. The contact had not taken the vehicle to the dealer to be diagnosed or repaired. The contact stated that the failure was related to NHTSA ID Number: 10207869 (Electrical System, Forward Collision Avoidance). The manufacturer was made aware of the failure and informed the contact that the rainstorm could have caused water to enter into the sensors for the automatic emergency brake to become defective. The approximate failure mileage was 17,000.
I was driving on the interstate in a construction zone and begin reducing speed from about 62 mph after noticing brake lights from cars in the far distance. As the car start to reduce speed, I begin to apply the brakes as I'm approaching the stopped traffic and instead of stopping my car kept going. I pressed the brakes harder, and the car began to slide. After sliding about 9-10 car lengths, I was stopped by rear ending the vehicle in front of me. There was an error message on the dash "Chassis Control System Error See Owner's Manual" that appeared on the dash. I was struck in the back by a Toyota 4Runner resulting in my car being totaled.
The contact owns a 2021 Nissan Altima. The contact stated that while in reverse, the back over prevention camera malfunctioned and images were displayed distorted at times or black and blue, creating a visibility hazard for the driver. The cause of the failure was not yet determined. The local dealer and manufacturer were notified of the failure, but no assistance was offered. The contact was informed that the VIN was not included in the NHTSA Campaign Number: 23V628000 (Back Over Prevention). The contact stated that the vehicle had experienced the failure listed in the recall The failure mileage was 49,000.
My car is supposed to have an automatic braking system/collision detection. Two cars in front of me slammed on their brakes and the car in front of me slammed on his brake, and I didn't have enough time to react. I totalled my car, but my car is supposed to have a safety feature that automatically brakes. The faulty automatic braking didn't engage as it should have.
Driving down the street a truck in front of the lady in front of me. It was a green light he decided to stop. She stopped I put I started to stop my brakes would not stop the car nor did the emergency front collision brakes work I could not stop the car.
Purchased the car in June of 2024 with around 33,000 miles. I thought the doors were locked and someone was able to just open my back door when my car was unattended in a store parking lot; the car was supposed to be locked. Lights and horn started going off. Being a female with a child this is a very scary issue. The idea that anyone can get in when you think the doors are locked or vice versa, in the event of an emergency no one can get in because the doors dont unlock. It started with the passenger side rear door lock not working with fob or button. The lock needs to be done manually. The dealership looked at it and said they could not replicate the problem and everything was working. Now both rear door locks dont work with the buttons or the key fob. The rear doors have to be locked and unlocked manually all the time. …
Vehicle Breaking on Its Own While Driving I am writing to file a formal safety complaint and to demand immediate corporate intervention regarding an extremely dangerous mechanical/ADAS defect. My Nissan Altima has serious, ongoing safety issues where the vehicle will unexpectedly and aggressively apply the brakes on its own while I am driving, including on highways and regular roads. This defect happens without my input, without warning, and creates a major risk of being rear-ended, losing control of the vehicle, or causing a serious accident. This issue is Not minor. It is a life-threatening malfunction that makes the vehicle unsafe to operate. …
The system malfunctioning is the front sensor braking. My safety and others were put at risk with this because multiple times my car has braked me and or completely stopped me because it's malfunctioning , it happens while I am on a busy street and someone even almost rear ended me because my car braked out of nowhere. It's called "Phantom Braking". No, the problem has not been confirmed by dealer became they stopped answering. I took it to the manufacture but they want to charge me too much. Yes and it first appeared Feb 2nd , a day after I bought the car. So at first it will aggressively brake me and I can tell when it's going to start braking me because this loud scratching/grinding noise appear .. the noise sounds like it's coming from the bottom and I can feel it vibrating my car when I relax my feet on the brakes or the floor. …
The Automatic Emergency Braking (AEB) system in my 2021 Nissan Altima SR frequently malfunctions. The forward radar sensor, located behind the front grille, becomes easily obstructed by normal road dirt or weather conditions. When this happens, the system falsely detects obstacles and engages braking or gives collision warnings even when the road ahead is clear. This places my safety and the safety of others at risk because the vehicle can suddenly slow or stop without cause, increasing the chance of a rear-end collision. To avoid false activations, I must disable the AEB system every time I drive, which defeats the purpose of having this federally mandated safety feature. The problem is ongoing and repeatable. Warning lights and collision alerts appear when the sensor is dirty or misreading conditions. …
Related recalls
Back over prevention › Sensing system › Camera
Nissan North America, Inc. (Nissan) is recalling certain 2019-2021 Altima and 2020-2021 Sentra vehicles. Damage to the camera harness can cause distortion or loss of the rearview camera display image.
Remedy: Dealers will inspect the rearview camera and harness for damage and replace them as necessary. If no damage is found, the dealer will apply protective tape and reroute the rearview camera harness.
Collision Avoidance complaints in other Altima years
Frequently asked questions
How common are collision avoidance problems on the 2021 Nissan Altima?
NHTSA has 25 complaints about the driver assistance of the 2021 Nissan Altima, 36% of the model year's 70 complaints. The component named most often is automatic emergency braking (18 mentions).
Is there a recall for 2021 Nissan Altima collision avoidance problems?
Yes — NHTSA recall 23V-628 (camera, Sep 8, 2023). Recall repairs are free at authorized dealers.
At what mileage do 2021 Nissan Altima collision avoidance problems start?
Half of the complaints with a recorded mileage happened before about 49,000 miles, and 50% before 25,000 miles.
Is it dangerous?
Owners linked 4 crashes, 0 fires and 2 injuries to driver assistance problems on this model year. If you notice symptoms, have the car checked before driving further.
Source: U.S. National Highway Traffic Safety Administration (NHTSA) — owner complaints through October 20, 2026, recalls and defect investigations; fuel economy from the EPA. Complaints are unverified reports and are not proof of a defect. How we rate model years.