Where is the AEB system located?
Automated emergency braking (AEB) is not a single component but a network of sensors and software that sit at the front of a vehicle, linked to the brakes. In most cars, the sensing hardware lives in the front end—a radar unit tucked in the lower bumper or grille and a forward-facing camera mounted near the top of the windshield—while the control electronics and the braking actuators are housed elsewhere in the vehicle.
Front-end sensors: how they’re positioned
The core AEB sensors are designed to monitor the road ahead and identify potential collisions. Their physical locations are chosen to maximize field of view and minimize obstructions.
- Radar sensor: typically embedded in the lower portion of the front bumper or behind the grille, scanning forward for vehicles and obstacles.
- Forward-facing camera: mounted high in the windscreen near the rear-view mirror or in a similar central location to read lane markings, traffic signs, and pedestrian shapes.
- Optional lidar or additional cameras: on some high-end or specialized models, one or more lidar units or extra cameras may supplement radar and main camera to improve detection in certain conditions.
- Additional sensors: a few systems include extra short-range sensors or corner sensors to assist in slow-speed or complex urban scenarios, though primary AEB relies on radar and camera.
In practice, the major systems rely on two primary sensing elements—radar and camera—positioned to maximize coverage of the road ahead and provide redundancy in challenging weather or lighting.
Where the control and braking hardware sits
The data from the front sensors is sent to an electronic control unit (ECU) that runs the AEB software. That control unit is usually part of the car’s broader ADAS or vehicle electronics architecture and may be located in the engine bay or behind the dashboard. When AEB detects a risk of collision, it issues a command to the braking system, which in most cars uses the standard hydraulic brakes controlled by ABS/ESC systems. In some newer or premium designs, there may be a brake-by-wire actuator integrated with the hydraulic system for more direct control.
The system’s performance also depends on the braking hardware and onboard safety networks, which coordinate with steering and traction control to reliably slow or stop the vehicle if necessary.
Regional differences and model variations
Where AEB sensors and controllers are located can vary by manufacturer and market. Key patterns include:
- European and many Asian models typically place the main camera behind the windshield and the radar unit in the lower bumper or grille, with the control module integrated into the ADAS stack.
- North American vehicles often follow similar layouts, but feature variations in sensor count and detection algorithms aligned with regional testing and crashes statistics.
- Some premium brands may add lidar or more cameras to expand capabilities, particularly for pedestrian and cyclist detection, or to enhance performance in poor weather.
Regardless of layout, the goal remains the same: detect hazards in time to brake automatically if the driver does not respond, using redundant sensors and robust control software to compensate for real-world conditions.
Summary
Automated emergency braking is a system built from front-end sensors (chiefly radar and a forward camera) plus a centralized control unit and the car’s braking system. The sensors are mounted at strategic locations on the front of the vehicle—radar in the lower bumper/grille and a camera behind the windshield—while the processing and braking commands are handled by the vehicle’s electronics and anti-lock braking system. Variations exist by manufacturer and market, but the basic arrangement remains consistent: front sensors, a central controller, and an automatic braking response when a collision threat is detected.
Can you turn off the AEB system?
You can turn the AEB feature off through the Settings menu of your infotainment system. If you adjust your AEB settings to “Off” or “Alert,” you may see a yellow icon in your vehicle gauge display as well as a message indicating that automatic braking has been turned off, depending on your vehicle.
What does it mean when the AEB warning light comes on?
When you see the AEB warning on your dash, it means there is a failure with your vehicle's driver-assistance auto-braking. You cannot rely on it until this is remedied, which could put you at risk. You could have an electrical malfunction or need a brake system check or flush.
Where is the AEB sensor located?
The AEB (Automatic Emergency Braking) sensor is typically located at the front of the vehicle, either as a radar sensor behind the grille or bumper, or a camera mounted behind the windshield near the rearview mirror. Some systems use both a radar sensor and a camera for comprehensive detection.
You can watch this video to see the location of the AEB radar and camera in a Nissan Altima: 24sNissan Canada Owners / PropriétairesYouTube · Sep 25, 2024
Radar sensor
- Location: Usually behind the front grille, bumper, or in a lower section of the bumper.
- Function: Measures the distance to other vehicles and objects using radar waves.
Camera
- Location: Typically mounted behind the windshield, near the rearview mirror, facing the road.
- Function: Identifies and classifies objects like pedestrians, vehicles, and lane markings.
Important considerations
- Obstructions: Dirt, snow, or other debris on the front of the vehicle can block the radar sensor, while smudges, glare, or frost on the windshield can block the camera.
- System warnings: If the system detects an issue with the sensors, a warning light may appear on your dashboard.
- Cleaning: Keep the front grille and the area of the windshield in front of the camera clean to ensure the system operates correctly.
How to fix an AEB light?
To fix an AEB system warning light, first try simple solutions like cleaning the sensors and camera lens, checking for obstructions on the windshield or grille, and verifying the parking brake isn't engaged. If the problem persists, a diagnostic scan for error codes, a recalibration, or a software update may be necessary.
This video explains how to fix the forward collision warning light by cleaning the windshield: 54sFixbookYouTube · Aug 3, 2025
Simple solutions
- Clean the camera lens and sensors:
- Clean the inside and outside of the windshield, especially around the area of the forward-facing camera.
- Use a soft cloth and a windshield cleaner to remove dirt, grime, or fog.
- Check the front radar sensor (often located behind the grille or emblem) for dirt or obstructions and clean it gently.
- Check for obstructions:
- Make sure nothing is blocking the sensors, such as snow, ice, or a dirty license plate.
- Ensure the parking brake is not engaged.
- Check fuses:
- Locate the fuse box and check for any blown fuses related to the AEB system or driver-assist features.
- Try a system reset:
- Some vehicles may benefit from a reset by disconnecting the negative terminal of the battery for a few minutes, then reconnecting it.
- Check your owner's manual to see if your vehicle has a specific reset procedure.
Professional solutions
This video demonstrates how to troubleshoot and fix forward emergency braking issues: 53sHVAC Mechanic YouTube · Dec 7, 2022
- Scan for trouble codes: A diagnostic scan can identify the specific fault code and the cause of the problem.
- Recalibrate sensors: If a sensor is knocked out of alignment by an impact, it will need to be recalibrated. This usually requires specialized equipment available at a dealership or professional mechanic.
- Update software: A software glitch can sometimes cause the warning light to appear. A dealership can check for and install any available software updates.
- Replace faulty components: If the sensors or wiring are damaged, they may need to be replaced. This often requires recalibration after replacement.
This video explains what to do if the AEB system doesn't work or has issues: 56sJon Suty Automotive RepairYouTube · Feb 2, 2023
