What is the problem with the collision mitigation system on the Honda CRV?

The Collision Mitigation Braking System (CMBS) on the Honda CR-V can brake unexpectedly or fail to brake when needed, due to sensor calibration, dirt or obstruction, or limitations in detection under certain conditions.

This article examines what CMBS is supposed to do, the kinds of problems CR-V owners have reported, common causes, and practical steps drivers can take to diagnose and address issues. It also looks at recalls or service campaigns that may affect CMBS across different model years.

What CMBS is and how it works

The Collision Mitigation Braking System is part of Honda Sensing, designed to reduce the severity of rear-end collisions by applying automatic braking if a collision with a vehicle ahead is deemed likely. CMBS uses a combination of millimeter-wave radar and a camera to assess distance, closing speeds, and potential hazards. When the system detects an imminent collision and the driver does not respond in time, it can apply enough braking force to slow the car. It is intended as a supplemental aid, not a substitute for attentive driving.

Common problems reported with CMBS in the CR-V

Various CR-V owners and reviewers have reported recurring issues with CMBS. The problems span unexpected braking, delayed or absent braking, and nuisance warnings. The list below captures the most frequently described scenarios.

• Unexpected or strong braking in light traffic or on dry roads, sometimes without any obstacle in the path


• Delayed braking or failure to brake when a vehicle rapidly slows in front, increasing the risk of a collision


• False positives where the system activates without a clear hazard, such as braking for oncoming lanes or empty intersections


• Reduced performance in adverse weather (rain, fog, snow) or on wet/icy surfaces


• Sensors misbehaving after windshield replacement, bumper work, or other cosmetic repairs, leading to calibration issues


• Warnings or alerts that appear without the system taking expected action, potentially causing driver confusion

In practice, riders and reviewers note that CMBS behavior can vary by model year, trim level, sensor conditioning, and road conditions, and it may respond differently in highway versus city driving.

What causes these problems

The issues with CMBS often stem from a mix of sensor, software, and environmental factors. The list below outlines common culprits that engineers and service technicians investigate when CMBS misbehaves.

• Sensor misalignment or damage after a collision, bumper replacement, or body work, which can throw off radar and camera readings


• Dirt, water, ice, or glare covering cameras or radar sensors, reducing detection accuracy


• Calibration requirements after windshield replacement, camera cleaning, or certain repairs that affect the sensor suite


• Software or firmware issues that may require updates or reprogramming by a dealer


• Weather and road conditions that can degrade sensor performance, such as heavy rain, snow, fog, or glare from sunlight


• Limitations in CMBS design, such as conservative braking thresholds or sensor blind spots at certain speeds or following distances

Owners should be aware that these factors can combine to produce inconsistent CMBS behavior, and diagnosing the root cause often requires a professional inspection with diagnostic tools.

What drivers can do

If you’re experiencing CMBS issues, these steps can help you identify and address the problem. The list below provides practical actions a CR-V owner can take before and during a dealer visit.

• Check for active recalls or service campaigns related to Honda Sensing or CMBS using your vehicle’s VIN on official databases and contact your dealer for confirmation


• Schedule a diagnostic appointment with an authorized Honda service center to inspect sensor alignment, clean lenses, and test CMBS performance


• Keep sensors and camera lenses clean and unobstructed; gently wipe the windshield area and bumper sensors if you notice dirt or moisture


• Avoid relying solely on CMBS; maintain a safe following distance and stay alert to traffic conditions, using brake pedal control as needed


• Ask about software updates or calibration procedures that may be required to restore proper CMBS function


• Document when CMBS misbehaves (weather, road type, speed, and whether it compares with other vehicles) to help technicians reproduce and diagnose the issue

Dealers may perform sensor recalibration, software updates, or more extensive inspections if misalignment or sensor faults are detected. Persistent issues should be thoroughly documented and addressed under warranty if applicable.

Recall and service information

There have been recalls and service advisories related to advanced driver-assistance features in various Honda models, including the CR-V, across different years. To stay current, CR-V owners should verify recall status and service campaigns tied to CMBS using their VIN and official sources.

• Use the VIN to check recalls at the NHTSA recall database or Honda’s official recall portal for open campaigns


• Contact your nearest Honda dealer to confirm recall status and arrange complimentary repairs or calibrations if a campaign applies


• If a recall is identified, avoid driving the vehicle if advised by the manufacturer or the dealer until the necessary service is completed

Proactive checking of recalls and service bulletins can help ensure CMBS is calibrated correctly and operating as designed, reducing risk and uncertainty on the road.

Summary

The Honda CR-V’s CMBS is intended to assist braking in potential collision scenarios, but owners have reported a range of reliability concerns—from unexpected braking to delayed or failed braking—driven by sensor calibration, environmental conditions, and maintenance history. Diagnosing and addressing these problems typically involves sensor cleaning, calibration after repairs, software updates, and, when necessary, professional inspection by a Honda dealer. Staying informed about recalls and service campaigns and driving with baseline defensive habits remain essential for safe operation.

Summary of key takeaways

In short, CMBS problems on the Honda CR-V are often tied to sensor issues, calibration, and environmental factors. Regular maintenance, timely software updates, and verification of recalls are the best strategies for keeping CMBS functioning as intended and reducing unexpected braking events.

What is the problem with the collision mitigation system on a Honda CR-V?

Honda CR-V collision mitigation system problems can stem from dirty sensors, misaligned cameras, a weak battery, or faulty radar units, and they often present as unexpected braking, false warnings, or a complete system failure. To troubleshoot, start by cleaning the front camera lens and radar sensor on the grille, and ensure the battery is in good condition. If the issue persists, a dealer may need to perform a sensor recalibration or a software update, as some problems are addressed by technical service bulletins (TSBs).
 
Common problems

• False activation: The system may activate the brakes or show warnings when there is no obstacle, sometimes triggered by everyday road conditions like shadows or bumps. 
• Failure to activate: In other cases, the system may fail to intervene when a collision is imminent. 
• Warning lights: You may see warning lights for the collision mitigation system, the road departure mitigation system, or other driver-assist features. 
• Inconsistent performance: The system's behavior can be spotty and unpredictable. 

What you can do

• Clean the sensors: A dirty front camera lens (behind the windshield) or radar sensor (in the front grille) is a common cause of problems. Gently clean both areas with a microfiber cloth. 
• Check the battery: A weak or failing battery can cause a host of electronic issues, including problems with the CMBS. 
• Adjust settings: Park the vehicle, turn the ignition on, and navigate to the Driver Assist System Setup menu to check or adjust the forward collision warning distance in the settings. 
• Consult the manual: Refer to your owner's manual for specific instructions on your model year. 

When to see a dealer

• If the problem continues after cleaning the sensors, take the vehicle to the dealership.
• The dealer can perform a diagnostic scan to identify specific sensor issues or misalignment.
• They may need to recalibrate the sensors or update the software, as some issues are addressed by technical service bulletins (TSBs). 

This video demonstrates how to clean the sensors and reset the CMBS warning light: 50sCarnivautoYouTube · Sep 1, 2025

How to fix 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. 

What is the class action lawsuit against Honda CR-V?

The class action specifically targets all 2018–2022 Honda CR-V SUVs sold or leased in California. These vehicles are alleged to share a common internal engine defect that can lead to failure without warning, potentially endangering drivers and passengers.

How to reset collision mitigation braking system Honda CR-V?

Again. Step five use an OBD2 scanner optional but recommended. If the light stays on connect an OBD2 scanner.