Toyota EV Recall Covers 20,991 bZ, RZ, Solterra

Toyota Motor Engineering & Manufacturing is recalling 20,991 model-year 2026 battery electric vehicles — the Toyota bZ, Lexus RZ, and Subaru Solterra — because a fault in the battery control unit can shut down the electric drive system and cause a loss of motive power while driving. The condition is covered under NHTSA recall 26V393, which Toyota filed as a voluntary safety campaign. Toyota estimates that 100% of the involved vehicles carry the affected software. Power steering and power-assisted braking continue to work when the fault occurs, but the drivetrain can stop delivering power.

Highlights

• 20,991 vehicles are involved across three model-year 2026 BEVs: the Toyota bZ (11,495), Lexus RZ (4,739), and Subaru Solterra (4,757).
• Toyota estimates 100% of the recalled vehicles contain a battery ECU running the affected software.
• The remedy is a free battery ECU software update at Toyota, Lexus, and Subaru dealers.
• Owner notification letters are scheduled to begin mailing August 3, 2026.

What Causes the Electric Drive System to Shut Down?

The recalled vehicles use an onboard battery ECU to control the high-voltage battery that powers the drivetrain. The unit contains two integrated circuits that share part of the same memory address location: a battery control IC and a monitoring IC. Under certain conditions, the monitoring IC can repeatedly overwrite data the battery control IC has just written to that shared address, and the memory can then fail an operational check.

Toyota’s bench testing found the repeated overwriting becomes more likely when the CPU’s memory operational check cycle lengthens — a situation an increase in CPU load can produce, such as when the battery is at a low state of charge. After multiple failed checks, the vehicle displays an “EV System Malfunction” warning, illuminates multiple malfunction indicator lamps, and the electric drive system shuts down. Power steering and power-assisted braking remain operational, but the resulting loss of motive power increases the risk of a crash. An engineering analysis also found that certain other systems, such as PCS and VSC, could become inoperable. The battery ECU carries part number 89890-42381 and is supplied by Denso Corporation.

Which Vehicles Are Affected

Toyota notes that not every vehicle built within these production windows was sold in the U.S. or carries the affected battery ECU software. The recall spans three model-year 2026 BEVs, including the Toyota bZ, the brand’s compact electric SUV.

How Toyota Identified the Problem

Toyota first observed the diagnostic pattern during development testing of a new plug-in hybrid model, then concluded its battery electric models would not experience the same condition because of a difference in the monitoring IC’s write cycle. A later review of remote diagnostic data from the BEV models already in production surfaced the same malfunction data, prompting bench testing that confirmed the overwriting could recur under longer memory-check cycles. Toyota decided to conduct the voluntary recall after that investigation. As of its review, the company had received no field technical reports and one warranty claim from U.S. sources that may relate to the condition.

Remedy and Owner Notification

Toyota, Lexus, and Subaru dealers will update the battery ECU software at no charge. Owner notification letters are scheduled to begin mailing August 3, 2026, with the planned remedy notification window running through August 17, 2026 as a phased recall. Owners who paid for a related repair before the campaign can seek reimbursement under Toyota’s general reimbursement plan, and Subaru will reimburse under the general plan it submitted in November 2025. Owners can reach Toyota customer service at 1-800-331-4331. Toyota’s internal recall numbers are 26LA07 and 26TA11; Subaru’s is WRG26.

Sign up for our popular weekly email to catch all the latest EV news!