Proterra Operating Company, Inc. (Proterra) is recalling certain 2020-2021 Catalyst and 2019-2022 ZX5 transit buses. Back pressure in the shared air exhaust for the pneumatic ride height system and parking brake control valve may engage the parking brake while the vehicle is in motion.
Unintentional engagement of the parking brake increases the risk of a crash.
Proterra will install a redesigned air circuit, free of charge. Owner notification letters were mailed on December 21, 2022. Owners may contact Proterra's customer service at 1-864-438-0000.
Owners may also contact the National Highway Traffic Safety Administration Vehicle Safety Hotline at 1-888-327-4236 (TTY 1-800-424-9153), or go to www.nhtsa.gov.