Toyota is expanding a recall from 2018 on certain Prius models that can stall while driving, according to paperwork filed with the NHTSA last week.
A transistor in the power module can fail when accelerating quickly and cause the hybrid system to shut down, which may cause the vehicle to stall and increase the risk of a crash. Repeated hard driving could cause more thermal stress on the transistors. When those transistors fail it can generate voltage higher than limits set by engineers. Exceeding that limit should trigger a failsafe mode that enables drivers to operate the car for certain distances. Instead, in the case of the recalled Prius, the system shuts down. Steering and braking are still operable, however. Drivers may be warned by warning lights and a warning message in the instrument panel.
The recall affects 266,638 models, including the 2013-2015 Prius and 2014-2017 Prius V.
Toyota didn't specify the percentage of recalled models affected by the issue. Toyota did specify those models were not included in the original recall from October 2018, when Toyota recalled 1.6 million Prius worldwide for the issue. Half of those recalled vehicles were in the U.S. That recall was labeled 18V-684.
The expanded recall is labeled 20V-369 with the NHTSA. All owners will be notified by August 10 and will be instructed to take their Prius to a dealer for a free software update. Owners can call Toyota customer service at 1-888-270-9371 and reference recall 20TB10/20TA10. Or owners can visit Toyota's recall website.