2017-2025 Honda CR-V: Solving 'Collision System Problem' & Replacing Radar Sensors

Symptoms of a Failing Collision Avoidance Sensor

Failure in the Honda CR-V's advanced driver-assistance systems (ADAS) almost always begins with a warning message on the driver information interface. While the sensors themselves are generally reliable, they are sensitive to damage, misalignment, and even simple obstructions.

• Dashboard Warning Lights: The most common symptom is a persistent warning message. You will typically see "Collision Mitigation System Problem," "Adaptive Cruise Control Problem," or "Blind Spot Information System Problem." Often, multiple warnings will appear at once, as several safety features rely on the same sensor data.
• Phantom Braking: A widely reported issue involves the Collision Mitigation Braking System (CMBS) applying the brakes suddenly and unexpectedly when there is no obstacle. This has prompted a large-scale NHTSA investigation into nearly 3 million Honda vehicles, including the 2017-2022 CR-V.
• System Unavailability: The systems may simply turn off and become unavailable for use. For example, you may be unable to engage Adaptive Cruise Control, or the blind spot indicator lights in the mirrors will never illuminate.
• False Alerts: The system may provide frequent, unnecessary collision warnings or blind spot alerts, even when no other vehicles are present.

Known Issues, TSBs, and Recalls

NHTSA Investigation into Phantom Braking

The National Highway Traffic Safety Administration (NHTSA) has upgraded a probe to an Engineering Analysis (a more serious step) concerning unexpected automatic emergency braking in 2017-2022 Honda CR-V and Accord models. The investigation was launched after receiving over 1,200 complaints, including reports of crashes and injuries, related to the CMBS activating without any actual obstruction. This indicates a potential widespread issue with the system's logic or sensor calibration, rather than isolated hardware failures.

Seat Weight Sensor Recall (Not a Radar Sensor)

Many 2017-2022 CR-Vs are part of a major recall (NHTSA ID: 26V332000) for a faulty front passenger seat weight sensor. This sensor can crack and short circuit, potentially causing the airbag to deploy improperly in a crash. While this is a critical safety recall, it is important to note that this part is located in the seat cushion and is not the same as the collision avoidance radar sensors in the grille or bumper.

Buying a Used Collision Avoidance Sensor

Given the high cost of new OEM radar sensors, a used, recycled OEM part is an excellent value. However, these are sensitive electronic components, and careful purchasing is key.

1. Match Part Numbers Exactly: This is the most critical step. Honda used many different part numbers throughout this generation, sometimes for the same location (e.g., left rear). A sensor from a different year or trim level may look identical but will not communicate with your vehicle's control modules. Always verify the number on your original part before buying a replacement.
2. Physical Inspection: When you receive the used sensor, inspect it carefully. Look for cracks in the plastic housing, damage to the electrical connector pins, and any signs of deep scratches or gouges on the face of the sensor. Do not accept a part with bent or broken mounting brackets, as this indicates it was likely damaged in a collision and may be internally misaligned.
3. Ask About the Donor Vehicle: If possible, find out the mileage of the vehicle the part came from. While these sensors don't have mechanical wear parts, choosing one from a lower-mileage vehicle is always preferable.
4. Why Used OEM is a Smart Choice: For a safety-critical part like a radar sensor, a recycled OEM unit that has been proven to work is often more reliable than a new, cheap aftermarket alternative. Aftermarket sensors may have different software or hardware tolerances, leading to calibration failures or poor performance.

Replacement and Calibration

Difficulty: 4 out of 5. While physically swapping the sensor is straightforward for a mechanic, the mandatory calibration process requires specialized equipment and software that most DIYers do not have.

Front Radar (CMBS/ACC): Replacing the front radar involves removing the front grille or bumper cover. After installation, the sensor must be aimed. This can be a static calibration, which uses a specialized stand with a radar reflector target placed at a precise distance and height in front of the vehicle, or a dynamic calibration, which involves driving the vehicle at certain speeds on well-marked roads while the system self-adjusts. A dealer or qualified ADAS shop uses a diagnostic tool like the Honda i-HDS to initiate and verify the procedure. 🎬 Watch this demonstration of Honda front radar camera calibration Some newer models may even require a live internet connection during the dynamic calibration process.

Rear Radars (BSI): These sensors are located behind the rear bumper cover, which must be removed for access. Like the front radar, these also require a specific aiming procedure after installation to ensure they are monitoring the correct zones. This also requires specialized targets and diagnostic software.

Cost Comparison

Prices for collision avoidance sensors can vary dramatically. The high cost of new OEM parts makes tested, used OEM sensors a very attractive option.

Part Number and Location Guide

The following is a list of known OEM part numbers. This list is not exhaustive, and part numbers are often superseded. Always confirm the part number on your specific vehicle before ordering.

Frequently Asked Questions (FAQ)