Toyota will recall nearly 7,000 vehicles—including many hybrids—for a faulty brake booster that could malfunction and impair those cars' brakes, the automaker announced last month.

The recall affects mostly 2019 model year cars and includes the Toyota Prius, Prius Prime, and RAV4 Hybrids built between late April and late May. A small number of 2020 Toyota Prius Prime and 2020 Corolla hybrids are included in the recall. The 2019 versions of Lexus UX 250h, LC 500h, LS 500h, and ES 300h hybrids are also affected, although their numbers are smaller compared to the Toyota hybrids. (Just one ES300h sedan will be recalled; two LS500h sedans will be recalled.)

2019 Toyota RAV4 Hybrid

2019 Toyota RAV4 Hybrid

According to paperwork filed with federal regulators, misshaped small brushes in the brake booster pump were improperly installed. Those brushes could become stuck in the holder and could cause the motor pump in the booster to stop operating. If it does, the braking assist could stop altogether and the vehicle's stability control systems could be disabled. Warning lights should illuminate on the dash if the malfunction occurs, according to Toyota.

Toyota said it discovered the issue in May 2019, and said it will begin notifying affected owners next month.

Toyota said one in four cars could potentially have the faulty brake booster, but the company didn't report any crashes or injuries related to the defect. One complaint registered with federal authorities reported that a 2019 Corolla crashed due to faulty brakes and injured its driver, although 2019 models were not included in the recall.

Toyota said it will replace the brake booster in affected cars for free.