Campaign 21V-734

Engine Control Unit (ECU) software may falsely detect an error and shut down the hybrid system, causing a loss of drive power

Defect summary

Toyota Motor Engineering & Manufacturing (Toyota) is recalling certain 2022 Prius and Prius Prime vehicles. The Engine Control Unit (ECU) software may falsely detect an error and shut down the hybrid system, causing a loss of drive power.

Consequence

A loss of drive power increases the risk of a crash.

Remedy

Dealers will update the ECU software, free of charge. Owner notification letters were mailed November 18, 2021. Owners may contact Toyota customer service at 1-800-331-4331. Toyota's number for this recall is 21TB07/21TA07.

Notes

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.

Source: NHTSA ODI recalls file, campaign 21V734000. Text as published by NHTSA.

Vehicles covered

2 product lines are covered

Owner complaints filed with NHTSA about engine and cooling on these vehicles: 4, of which 0 involved a crash, fire, injury or death. Complaints are not verified by NHTSA.

Vehicles covered by campaign 21V-734
Make	Model	Model years	Complaints on this component
Toyota	Prius	2022	3
Toyota	Prius Prime	2022	1

Source: NHTSA ODI recalls and complaints files. Equipment, tire and child-seat campaigns list products, not vehicles.

Investigation

No NHTSA investigation is linked to this recall

Most recalls are started by the manufacturer. This one lists "Manufacturer" as its origin.

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