TSB: Some 2014 ? 2018 model year Corolla and 2017 ? 2018 model year iM vehicles equipped with the K313 Continuously Variable Transaxle (CVT) may exhibit a high-pitched hiss or whine noise after the vehicle has reached normal operating temperature. This condition may be caused by the valve body plate inside the CVT assembly. Follow the Repair Procedure in this bulletin to address
this condition.
