2017 Proterra Catalyst problems

What is wrong

Proterra Operation Company, Inc. (Proterra) is recalling certain 2017-2019 Catalyst transit buses. One or more battery packs may allow liquid to leak into and accumulate in the battery pack enclosure.

Risk

The accumulation of liquid inside the battery pack enclosure increases the risk of a fire.

Remedy

Proterra will update software, inspect, and replace the battery pack, free of charge. Owner letters were mailed November 6, 2023. Owners may contact Proterra's customer service at 1‑864‑438‑0000.

Recall number 22V887000 · Recall details

What is wrong

Proterra, Inc. (Proterra) is recalling certain 2017-2019 35 foot Catalyst E2, 2017-2019 40 foot E2, 2020-2021 35 foot RR, 2019-2020 40 foot RR, 2019-2022 40 foot ZX5, and 2020-2022 35 foot ZX5 buses. The plexus adhesive between the torque limiter plate and the bus body may be insufficient, causing the bolts that secure the steering gearbox to loosen.

Risk

A loose steering gearbox can cause a loss of steering control, increasing the risk of a crash.

Remedy

Dealers will install a mechanical fastener and new bolts on the steering gearbox, and install a new torque plate, as necessary, free of charge. Owner notification letters were mailed October 7, 2022. Owners may contact Proterra's customer service at 1‑864‑438‑0000.

Recall number 22V114000 · Recall details

What is wrong

Proterra, Inc. (Proterra) is recalling certain 2017-2018 Catalyst buses. The vehicles are equipped with swivel valves that may insufficiently protect the air brake system from an air leak between the service reservoir and the source of air pressure. As such, these vehicles fail to comply with the requirements of Federal Motor Vehicle Safety Standard (FMVSS) number 121, "Air Brake Systems."

Risk

If the swivel valves are unable to protect the air brake system against loss of air pressure, this may lead to service brake failure and the possibility for the uncontrolled application of the safety brake. Either condition increases the risk of crash.

Remedy

Proterra will notify owners, and will replace the swivel valve with a check valve that is sufficient to protect the air brake system, free of charge. The recall began July 26, 2019. Owners may contact Proterra customer service at 1‑864‑438‑0000.

Recall number 19V402000 · Recall details

What is wrong

Proterra, Inc. (Proterra) is recalling certain 2015-2018 Catalyst 40 buses equipped with an optional tow fitting and airline that allows a tow truck to operate the rear brakes on the vehicle. The mesh cap covering the airline for the tow fitting can be clogged with road debris in inclement weather, possibly resulting in a build up of air pressure in the rear brake system.

Risk

A build up of air pressure can cause the brakes to drag and possibly overheat, increasing the risk of fire.

Remedy

Proterra will notify owners, and dealers will install an additional shield to the tow fitting that protects the mesh cap, free of charge. The recall began June 4, 2019. Owners may contact Proterra customer service at 1‑864‑438‑0000.

Recall number 19V283000 · Recall details

What is wrong

Proterra Inc., (Proterra) is recalling certain 2015-2018 Catalyst 40 and 35 transit buses. The affected vehicles are equipped with a four point height control system that may cause a load imbalance, overloading the front tires.

Risk

An overloaded front tire may fail unexpectedly, increasing the risk of crash.

Remedy

Proterra will notify owners, and dealers will convert the current four point ride height system into a three point system to prevent the front tires from being overloaded, free of charge. The recall began March 26, 2019. Owners may contact Proterra customer service at 1‑864‑438‑0000.

Recall number 19V062000 · Recall details

What is wrong

Proterra Inc., (Proterra) is recalling certain 2015-2018 Catalyst 40 transit buses. The affected vehicles lack a Graham White air brake supply reservoir, possibly resulting in long term moisture build up in the air brake system. As a result, these vehicles fail to comply with Federal Motor Vehicle Safety Standard (FMVSS) number 121, "Air Brake Systems."

Risk

Built-up of moisture in the air brake system may lead to brake failure, increasing the risk of crash.

Remedy

Proterra will notify owners, and dealers will install a supply reservoir with a drain between the air dryer and the air supply manifold, free of charge. The recall is expected to begin March 28, 2019. Owners may contact Proterra customer service at 1‑864‑438‑0000.

Recall number 19V061000 · Recall details

What is wrong

Proterra, Inc is recalling certain 2015-2018 Catalyst 40, and Catalyst 35 buses. The certification label may list an incorrect gross front axle weight rating and/or incorrect tire pressures. As such, these vehicles fail to comply with the requirements of 49 CFR Part 567, "Certification."

Risk

If the tire pressure is understated, an underinflated tire may result in an increased risk of tire failure, increasing the risk of a crash.

Remedy

Proterra will notify owners, and dealers will replace the certification labels with correct information for all affected customers, free of charge. The recall began March 12, 2019. Owners may contact Proterra customer service at 1‑864‑438‑0000.

Recall number 19V034000 · Recall details

What is wrong

Proterra is recalling certain 2016-2017 Proterra Catalyst 40 transit buses equipped with axles with radial air disk brakes. Surface roughness of a guide pin in the radial brake calipers may cause the brake carriage guide pin support bolt to break.

Risk

Breakage of the guide pin can cause loss of braking ability or loss of tire pressure, increasing the risk of a crash.

Remedy

Proterra will notify owners and have them replace the calipers on the affected axles, free of charge. Owners may contact Proterra customer service at 1‑864‑438‑0000.

Recall number 18V750000 · Recall details

In November 2022, Proterra Operating Company, Inc. (Proterra) filed a safety recall (the federal safety agency recall 22V887) covering nineteen 2017-2019 Proterra Catalyst transit buses to address the potential of liquid accumulation in the 400-volt battery packs, increasing the risk of a fire. On December 16, 2022, Proterra mailed an interim owner notification letter stating that Proterra would physically inspect and analyze each recalled battery pack.In October 2023, Proterra amended their filing to now cover 300 vehicles, with a final remedy plan of updating the battery monitoring software. According to the final remedy documents from Proterra, should liquid be detected within the battery pack, the updated software would illuminate a warning light in the driver's dash display, prevent the batteries from being charged, and reduce the maximum speed of the buses.As of the most recent recall completion rate report, 109 of the 300 buses (36.3%) have received the software update. In August 2023, Proterra declared bankruptcy, with its the three major business areas going to three separate companies.Phoenix Motorcars assumed liability for recall 22V887. On June 5, 2025, a fire occurred at the Southeastern Pennsylvania Transportation Authority (SEPTA) decommissioning lot.Local officials stated that the fire initiated in a battery pack of one of the Proterra buses. The Office of Defects Investigation (ODI) is opening this Recall Query (RQ) to evaluate the remedy effectiveness of recall 22V887 and to further understand the effects of nearly two-thirds of the affected population having not yet received the recall remedy.

RQ25001