Acura->ke10 is recalling nearly 50,000 MDX->ke1875 SUVs->ke145 and RLX->ke4673 sedans->ke142 over an issue affecting the emergency braking system, which can malfunction and apply the brakes without warning, putting the vehicle at risk of a collision. The recall was issued for the 2014 and 2015 model years and concerns vehicles sold worldwide.

The issue stems from Acura’s ironically named “Collision Mitigation Braking System,” which uses radar to scan the road ahead of the vehicle. When functioning properly, the system will apply the brakes when it detects an unavoidable collision with a slow moving or stationary object, decelerating the vehicle and lessening the likelihood of injuries and damage.

According to Honda,->ke34 Acura’s parent company, it’s possible that the system in the recalled vehicles will malfunction when it detects a vehicle accelerating in front while simultaneously driving parallel to an iron fence or metal guardrail, unnecessarily applying the brakes and possibly causing a rear-end collision.

The issue first came to light in Japan in November of 2013 when an SUV outfitted with the CMBS unexpectedly braked, causing a rear-end collision. Honda moved to investigate, while a second, similar incident occurred in June of last year.

Honda subsequently managed to duplicate the issue, determined the cause, and informed safety regulators of the recall in May. So far, there have been no reports of warranty claims, incidents, or injuries in the U.S. connected with the malfunction, and dealers will update the system software free of charge.

Later versions of the system, which stop the vehicle altogether before a crash, are unaffected by the recall.

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Why it matters

This isn’t the first time that an autonomous braking system has been recalled. Last week, the National Highway Traffic Safety Administration launched an investigation into complaints over unexpected braking in the 2014 Jeep Grand Cherokee, which uses a similar system to that found in the Acuras.

Acura MDX

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Acura RLX

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