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How do you reset the braking system on a Honda collision mitigation?

There isn’t a simple consumer reset for Honda’s Collision Mitigation Braking System (CMBS). If the warning light or fault message persists, seek authorized service. In many cases, CMBS will recalibrate after sensor cleaning and normal driving, but persistent faults require professional diagnostics.

How CMBS works in Honda vehicles

CMBS uses a forward-facing camera and radar sensor to detect potential collisions and apply braking automatically to reduce impact. It is an assistive safety feature designed to complement driver braking, not replace it. Sensor alignment, dirt, ice, glare, and weather conditions can affect performance.

Key components

In most Honda models, a forward camera near the top of the windshield and a radar sensor behind the front grille or bumper provide data to the CMBS. The system shares data with ABS, traction control, and other safety features.

Is there a user-initiated reset?

Unlike some maintenance features, CMBS typically cannot be reset with a simple button press. If the system indicates a fault, it requires diagnostic inspection with Honda’s service tools. Some models may briefly reset after power cycles or sensor cleaning, but a persistent issue requires service.

Before attempting any steps, ensure you are parked safely and ready to handle potential sensor cleaning tasks.

Inspect and clean the forward camera and radar sensors: The camera is usually behind the windshield close to the rearview mirror; the radar sensor is behind the front grille or bumper. Clear any dirt, ice, or debris that could block data input.

Remove obstructing materials and verify there are no aftermarket accessories or damaged components that could affect the sensor's field of view.

Check the windshield and area around the camera for cracks or significant damage that could impair imaging.

Verify tires are inflated to manufacturer specifications and that wheel alignment is correct; uneven wear or incorrect pressure can affect all safety systems that rely on sensors and vehicle dynamics.

Cleaning and basic checks may resolve false warnings in many cases; however, if the CMBS warning persists after these steps, do not drive aggressively and seek professional service.

What a Honda dealer will do to reset or recalibrate CMBS

When a diagnostic is required, technicians use Honda's proprietary software to read fault codes, calibrate sensors, and confirm proper operation. A dealership or certified shop typically performs these steps:

Run a full CMBS diagnostic to read fault codes and system history.

Calibrate or realign the forward camera and radar sensor using factory tools; this requires precise reference points and may involve multiple test drives.

Inspect wiring, connectors, and power supply to the CMBS components for any damage or corrosion.

Replace faulty components (camera, radar unit, or related hardware) if the fault cannot be cleared by calibration.

Perform a final system validation including a road test to ensure CMBS engages appropriately without false activations.

After a professional reset or calibration, CMBS should return to normal operation, but ongoing issues should be reported back to the service center for follow-up.

Safety considerations and model variations

CMBS is an assistive safety feature. Drivers should maintain adequate following distance, avoid relying solely on automated braking, and understand that system performance can vary by weather, road conditions, and sensor cleanliness. Model year and trim can affect the exact calibration and service procedures, so consult your owner’s manual or a dealer for model-specific guidance.

Summary

There is no simple consumer reset for Honda’s Collision Mitigation Braking System. If CMBS reports a fault or warning, cleaning and inspecting the sensors can resolve some false alarms, but persistent issues require professional diagnostic work and calibration. Regular maintenance, safe driving habits, and model-specific guidance from Honda or a certified dealership are essential to keep CMBS functioning properly.

How to clear a collision mitigation system problem?

To fix a collision mitigation system problem, first try cleaning the sensors and cameras on the front of your car, as dirt and debris are common causes. Next, ensure your car's battery is fully charged and its connections are secure. If the issue persists, restart the vehicle, or try resetting the system through your car's settings menu.
Step 1: Clean the sensors and camera

Clean the radar sensor: Wipe the sensor, which is often located behind the front emblem, with a soft cloth.
Clean the windshield camera: Clean the area of the windshield where the camera is located, as smudges can cause issues.

This video demonstrates how to clean the sensors and camera to fix collision mitigation system problems: 57sDashboard warning lights YouTube · Sep 4, 2025
Step 2: Check the battery

Charge the battery: A weak battery can often trigger the warning light. Make sure it is fully charged.
Secure the connections: Check that the battery terminals are tight and clean.

Step 3: Reset the system

Restart the car: Turn the vehicle off completely, wait about 30 seconds, and then restart it.
Reset via settings: Navigate to your car's settings menu, find the driver assistance or safety system setup, and try turning the collision mitigation system off and then back on again.
Disconnect the battery (advanced): As a last resort, you can disconnect the negative battery terminal for a few minutes, then reconnect it. This will reset the car's electronics.

This video shows how to reset the collision mitigation system by disconnecting the battery: 56sCar FixYouTube · Jul 2, 2025
Step 4: Check for other issues

Check brake fluid: Low brake fluid can sometimes cause warnings for safety systems, so check your fluid levels.
Consider alignment: In some cases, a steering wheel that is not centered can cause the system to malfunction. An alignment may be necessary.
Consult an expert: If the problem continues, it may be a more complex issue like a faulty sensor or software glitch. You may need to use an OBD2 scanner to read error codes or take the vehicle to a dealer for professional diagnosis.

Why is my collision mitigation braking system light on?

A constant collision mitigation light often indicates sensor misalignment, dirt, or malfunction in the radar or camera system. Start by cleaning the front grille and windshield area where sensors are located. Next, check for any physical damage or loose wiring to the radar unit behind the grille.

What is the problem with Honda collision mitigation braking system?

Common problems with the Honda Collision Mitigation Braking System (CMBS) include false alarms, unreliable braking, and sudden engagement. Issues can be triggered by external factors like weather, road conditions, or sensor obstruction, but can also be caused by internal problems such as a weak battery, misalignment, or a low brake fluid level. For a persistent problem, a dealer visit is necessary to diagnose and repair issues like a misaligned radar or camera.
This video explains how to fix the collision mitigation braking system problem by cleaning the sensors: 50sCarnivautoYouTube · Sep 1, 2025
Common problems and causes

False alarms and phantom braking: The system may trigger unexpectedly or fail to engage when needed due to misinterpreting shadows, road conditions, or obstacles.
Sensor obstruction: Dirt, snow, fog, or other debris on the front grille or sensors can cause the system to malfunction or turn off.
Misalignment: A minor front-end impact, even without visible damage, can misalign the radar sensor, affecting its performance.
Weak battery: Low voltage can cause various safety systems, including the CMBS, to act erratically.
Low brake fluid: This can trigger a "Check Brake System" warning and affect the functionality of the braking system.
Steering wheel not centered: An improperly aligned steering wheel can cause multiple dashboard warnings, including issues with the CMBS and other safety features.
External factors: Driving in heavy rain, fog, or snow can cause the CMBS to temporarily shut off.

You can watch this video to see how a weak battery can cause various warnings, including the CMBS problem: 53sTimz AutoYouTube · Jan 14, 2023
What to do

Check for obstructions: Clean the front of the vehicle, especially the area around the Honda emblem, and check for any dirt or debris.
Inspect fluids: Check your brake fluid level. A low level is a common cause of "Check Brake System" warnings.
Test the battery: Have your battery tested to ensure it's holding a charge. A weak battery can cause a host of electronic issues.
Check for alignment: If your car has had any recent front-end contact, even a minor bump, it may need a wheel and radar alignment from a dealership.
See a dealer for persistent issues: If simple checks don't resolve the problem, it's best to take the vehicle to a dealer. They can run diagnostics to pinpoint and fix issues like misaligned sensors or other internal problems.

How to reset Honda collision mitigation braking system problem?

To reset a Honda Collision Mitigation Braking System (CMBS) problem, first try turning the vehicle off and on again, as this will often clear temporary glitches. If that doesn't work, you may need to manually turn the system off and then restart it, or for a more complete reset, disconnect the negative battery terminal for a few minutes before reconnecting it.
Method 1: Restart the vehicle

This is the simplest first step to try.
Turn your vehicle completely off.
Wait for at least a minute.
Restart the engine and check if the warning light or error message has disappeared.

This video demonstrates how to reset the collision mitigation system by restarting the car: 57sDashboard warning lights YouTube · Sep 4, 2025
Method 2: Manually turn the system off and on

CMBS will automatically reset to the "on" position every time you start the engine.
Turning it off and then back on can resolve certain errors.
To turn it off, press and hold the CMBS OFF button until a beep sounds and the indicator appears.
Restart the vehicle to see if the system has been reset.

Method 3: Disconnect the battery

This is a more thorough reset and should be performed with caution.
Disconnect the negative battery cable.
Wait a few minutes.
Reconnect the negative cable.
Start the car and let it idle for a few minutes before driving.

This video shows how to disconnect the car battery for a system reset: 58sCarnivautoYouTube · Sep 1, 2025
Important considerations

If the problem persists after trying these resets, there may be an underlying issue with a sensor or a component that requires professional diagnosis and repair by a dealership.
The system can also automatically shut off due to poor weather conditions (like heavy rain or snow) or if the sensors are obstructed. Check for any blockages on the grille and clean the sensors before performing a reset.
For a permanent solution to a specific problem, such as a faulty sensor, professional service is recommended.

Kevin Bennett

Company Owner

Kevin Bennet is the founder and owner of Kevin's Autos, a leading automotive service provider in Australia. With a deep commitment to customer satisfaction and years of industry expertise, Kevin uses his blog to answer the most common questions posed by his customers. From maintenance tips to troubleshooting advice, Kevin's articles are designed to empower drivers with the knowledge they need to keep their vehicles running smoothly and safely.