

About this problem
Automatic emergency braking uses a camera, a radar sensor or both to watch the road ahead and brake hard if a crash looks likely. The problem owners report is "phantom braking": the system slams on the brakes for a shadow, an overpass, a parked car or nothing at all. That can startle the driver and risk a rear-end crash from the car behind. Software updates have reduced it on some models but not all.
Across all owner complaints filed about the Nissan Altima since 2012, 103 (1.6%) describe automatic emergency braking problems, the third most reported problem we track on the Altima. The reports cluster on the 2018, 2019 and 2020 model years, and the 2019 drew the most, with 26. It tends to show up early in the car's life: half of the owners who gave a mileage were between 8,000 and 43,000 miles. 16 reports describe a crash or fire linked to it. No recall covers it, but Nissan has sent dealers service bulletins about it, listed below.
What owners report
Owners describe the Altima braking hard on its own, often at highway speed with nothing in the way: under bridges, past parked cars, in shadows or around curves. Some report the warning chime and a jolt; others report the car slowing sharply enough to risk being rear-ended. The complaints cluster in the 2018 to 2020 model years, the first years this system became standard on most trims.
How it gets fixed
Carmakers have released software updates for many of these systems, and some owners report the problem eased after a dealer update or a camera and radar recalibration. A dirty or misaligned windshield camera, or a replaced windshield that was not recalibrated, can also cause false alarms.
Typical cost: A software update is usually free under warranty. A camera or radar recalibration after windshield work typically costs $150 to $400 at a shop.
Complaints by model year
In owners' words
"The aeb (automatic emergency braking) system malfunctions continuously. I get a warning (front senors unavailable due to obstruction) but there is no obstruction. This shuts off the safety system that was designed to sense and stop the vehicle in an emergency."
2018 Nissan Altima, 14,500 miles
"My vehicle was in motion on a city street. I went to make a turn because of a curve and my steering wheel and brake would not work. My emergency brake system (which is suppose to stop my vehicle before impact, did not deploy."
2019 Nissan Altima, 14,000 miles
Excerpts from public owner complaints filed with the National Highway Traffic Safety Administration, lightly trimmed.
Service bulletins
Nissan has sent dealers 7 bulletins that mention this problem on the Altima. A bulletin tells technicians how to fix a known fault. It is not a recall, so the repair is usually free only while the car is under warranty or covered by an extension.
AUTOMATIC EMERGENCY BRAKING WARNING LIGHT BLINKING This bulletin has been amended.
FALSE ACTIVATION OF AEB OR FCW APPLIED VEHICLES: 2021-2022 Altima (L34) 2022-2023 Frontier (D41) 2020-2022 Sentra (B18) APPLIED DATES: Altima: All Frontier: All Sentra: Built on or before March 10, 2022 APPLIED SYSTEMS: Automat...
FALSE ACTIVATION OF AEB OR FCW IF YOU CONFIRM The customer states they have experienced false activation and/or unexpected braking of the Automatic Emergency Braking (AEB) or Forward Collision Warning (FCW) system, AND There ar...
ADAS SYSTEM DTC C1A03, C1A04, AND/OR C1B01 SERVICE INFORMATION This bulletin applies only to vehicles equipped with Automatic Emergency Braking (AEB) or Forward Emergency Braking (FEB).
Nissan; DIAGNOSIS INFORMATION FOR ABS DTC C1130 SERVICE INFORMATION When diagnosing for DTC C1130 (ENGINE SIGNAL): ECM related DTCs (P-codes) must be diagnosed, repaired, and DTCs erased first.
Before you buy a Altima
- Drive the car on a busy road with parked cars, overpasses and shadows, where false braking tends to happen.
- Ask whether the braking software has been updated, and check for open recalls by VIN.
- If the windshield was replaced, ask for proof the camera was recalibrated.
Questions
Which Nissan Altima years have automatic emergency braking problems?
Complaints are highest for the 2018, 2019, 2020 model years. The 2019 drew the most, with 26 reports.
At what mileage does it usually start?
Among owners who gave a mileage, the middle figure was about 21,000 miles, and half reported it between 8,000 and 43,000 miles.
How much does it cost to fix?
A software update is usually free under warranty. A camera or radar recalibration after windshield work typically costs $150 to $400 at a shop.