Not everyone who ordered the front collision prevention system on their 2021 Toyota C-HR got it and, worse still, the fault means that the system can fail without warning to the driver. That’s leading to a recall of the vehicle, National Highway Traffic Safety Administration documents reveal.

The issue lies with radar sensors that weren’t properly initialized at the vehicle assembly plant in some C-HRs built between June 12, 2020, and July 26, 2021. The good news is that, although Toyota’s recall population potentially affects 36,558 vehicles, just 0.03 percent of them are actually expected to be afflicted by the faulty sensor.

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Unfortunately, the nature of the issue means that the vehicle will not display an error message and the owner will not be notified that there anything is amiss with their front collision prevention system. Beyond the customer being denied a feature they ordered, it could also lull them into a false sense of security.

The vehicles whose sensors weren’t properly initialized aren’t able to detect a vehicle in front of them and, therefore, cannot provide warnings or braking assist as intended.

Toyota expects to start notifying owners of the fault on April 11 and they will be asked to take their vehicle to a dealership. All vehicles involved will have their radar sensors inspected and, if necessary, they will be properly initialized, free of charge.