Phantom Braking: Why Cars Brake for No Reason, and Which Models Draw Complaints

Phantom braking is a sudden, unexpected slowdown caused by a car’s own driver-assistance system, usually automatic emergency braking or adaptive cruise control, when it mistakes something harmless for an obstacle. This guide explains why it happens, shows from NHTSA’s complaint file how often owners report problems with these systems and which models draw the most reports, and covers the investigations, recalls and new federal rule, plus what to do if it happens to you.

What phantom braking is

Most new cars watch the road ahead with a camera, a radar sensor or both. Three related features use them:

• Forward collision warning sounds an alert when a crash looks likely.
• Automatic emergency braking (AEB) brakes on its own if the driver doesn’t react in time.
• Adaptive cruise control keeps a set gap to the vehicle ahead by braking and accelerating.

Phantom braking happens when one of these systems decides there is a threat and brakes, sometimes firmly, with nothing in the car’s path. NHTSA groups owner complaints about all three under one component, “forward collision avoidance,” so the complaint counts below include other problems with the same systems, such as warnings that don’t stop or braking that doesn’t happen when it should.

What causes it

Automakers rarely publish a full explanation, but the investigations and the new federal test point to the usual suspects:

• Things on or beside the road. Shadows, overpasses, metal plates and parked cars at the roadside are commonly blamed for confusing a camera or radar. The federal false-activation tests described below use exactly these: a steel plate on the road and a gap between two parked vehicles.
• Sensor changes and software. In closing its Tesla investigation, NHTSA pointed to Tesla’s move from radar to camera-only sensing as a likely factor, and said Tesla pushed software updates in early 2022 aimed at the problem.
• Dirty, blocked or misaligned sensors. Snow, mud, a cracked windshield or a sensor knocked out of alignment can degrade the system. FMVSS 127 requires AEB to warn the driver when a blocked sensor degrades it.
• Hardware or software defects. Some cases are recalls: the automaker found a defect that makes the system brake unexpectedly, as in the campaigns listed below.

How common are complaints?

Forward collision avoidance has become one of the fastest-growing complaint categories, simply because the systems spread from a few luxury cars to almost every new vehicle:

One complaint can name several components. Recent model years are still collecting reports. Source: NHTSA owner complaints file, retrieved Oct 6, 2026; computed by PlainVIN.

For the newest model years, these systems are named in roughly one complaint in eight. Our analysis of the most common car problems shows how they have overtaken air bags as a complaint category for newer cars.

Which cars have the most complaints

Counts of owner reports, not verified defects or rates; models that sold in larger numbers draw more complaints. The share compares with all complaints for that model over the same model years. Source: NHTSA owner complaints file, retrieved Oct 6, 2026; computed by PlainVIN.

Two groups stand out. For the Tesla Model 3 and Model Y, forward collision avoidance makes up a very large share of all complaints, far more than for any mainstream model. For the Honda CR-V, Accord, Odyssey and Pilot, the counts are high partly because these are big sellers, but the share is still well above the average for vehicles of the same years. The single model years with the most reports:

Source: NHTSA owner complaints file, retrieved Oct 6, 2026; computed by PlainVIN.

Complaint counts are owner reports, not verified defects, and models that sold in large numbers draw more of every kind of complaint. Use them to spot a pattern worth asking about, then look at the model-year report for the full picture, for example the Tesla Model Y, Honda CR-V or Honda Accord.

What NHTSA has done: investigations and recalls

Tesla. NHTSA opened a preliminary evaluation (PE22-002) in February 2022 into unexpected braking in about 416,000 2021–2022 Model 3 and Model Y vehicles. It closed the probe in July 2026. As reported by Quartz, complaints fell from about 300 when the probe opened to 45 in 2024, 19 in 2025 and three in 2026. NHTSA found no crashes attributed to the problem and noted that closing the probe doesn’t rule out a defect (Quartz via Yahoo Autos, July 2, 2026). Our complaint data shows the same pattern: Tesla’s forward collision avoidance complaints peak in the 2021 and 2022 model years.

Honda. In April 2024 NHTSA upgraded its Honda investigation, opened in 2022, to an engineering analysis covering nearly 3 million 2017–2022 CR-V and 2018–2022 Accord vehicles. The Associated Press reported that the agency had 1,294 complaints, 47 crash reports and 112 injury reports alleging that the system braked with nothing in the vehicle’s path (AP via NBC New York, April 17, 2024). An engineering analysis is the last step before NHTSA can seek a recall; check NHTSA’s site for the current status.

Recalls. Some automakers have recalled vehicles because their systems could brake unexpectedly. 10 campaigns in NHTSA’s file fix unexpected braking from a forward collision avoidance system, covering 601,044 vehicles:

Vehicle descriptions are NHTSA’s own summary wording; “repaired” is the share the manufacturer reports as fixed, and new campaigns start near zero. Source: NHTSA recalls file and US DOT completion data, retrieved Oct 6, 2026.

Across all recalls that list a forward collision avoidance component, 52 campaigns since 2014, 60% mention software. Many are fixed with a software update at the dealer or over the air.

The new federal AEB rule

Until now, AEB was voluntary in the US. Federal Motor Vehicle Safety Standard 127 makes it mandatory for cars, SUVs, pickups and vans built on or after September 1, 2029, and it is the first standard to test for false braking:

“The vehicle must not automatically apply braking that results in peak additional deceleration that exceeds what manual braking would produce by 0.25 g or greater, when tested using the procedures in S9 under the conditions specified in S6.”49 CFR 571.127, S5.3 (False activation)

The test drives the vehicle at 80 km/h (about 50 mph) over a steel trench plate laid on the road and between two stationary vehicles parked 4.5 meters apart, the kind of roadside scene that can confuse sensors. The same standard requires AEB to detect when its sensors are blocked and warn the driver. Until 2029, how well a car avoids false braking depends on the automaker.

What to do if your car brakes for no reason

1. Stay in control. Keep a firm grip and check your mirrors. Your owner’s manual explains how your system behaves, including whether pressing the accelerator cancels an automatic brake application.
2. Write it down. Note the date, time, speed, weather, road and what was around you. Dashcam footage helps. A dealer can’t fix what it can’t reproduce, a frustration many Honda owners described to NHTSA.
3. Check for recalls and updates. Enter your VIN at nhtsa.gov/recalls and install pending software updates; several of the recalls above are software fixes. Our guide shows where to find the VIN.
4. Have the sensors checked. Ask the dealer to inspect, clean and calibrate the camera and radar, especially after a windshield replacement, a bumper repair or a minor collision. Ask whether a technical service bulletin covers the problem.
5. Know your settings. Many vehicles let you change how early the system warns or turn some features off for a trip, and in many the system switches back on the next time you start the car. Turning off a safety system has trade-offs, so use the manual’s guidance.
6. Report it to NHTSA. Complaints are how investigations start; the Honda and Tesla probes began with them. Our guide explains how to file a complaint with NHTSA.

Buying used? Look up the model year’s owner complaints by component before you buy, and include a highway test drive with the driver-assistance features switched on. Our used car inspection checklist covers the rest.

Complaint and recall figures are PlainVIN’s analysis of NHTSA’s files and update when we refresh the data; complaints are owner reports, not verified defects. This guide is general safety information, not professional advice.