2026 Toyota C-HR Recall: Loss of Drive Power from Software Programming Error

A cold morning, a drive battery charged to full overnight, and a long descent ahead. On a 2026 Toyota C-HR, that combination can push regenerative braking into a pack that has no room left for the charge. The software meant to cap charging does not, the battery overcharges, and the electric drive system shuts itself down while the car is still rolling at speed, with warning lights and a buzzer marking the shutdown.

Toyota filed NHTSA campaign 26V570000 on September 2, 2026, covering 8,521 battery-electric C-HRs built between February 6 and July 10, 2026. Toyota's internal number is 26TA17. The fix is a software update to the battery electric vehicle ECU, and the company found it after spotting a bad parameter while testing a model it has not put on sale yet.

Toyota lists the estimated percentage with the defect at 100 percent. Every car in the population runs the software; whether a given car shuts down depends on temperature, state of charge and how long it spends in regenerative mode.

The Issue

The BEV ECU manages the high-voltage drive battery, and one of its jobs is drive battery protection logic that limits how much charge goes in. Toyota's Part 573 filing traces the recall to an incorrect parameter in that logic, the value used for battery charging control. With the wrong number in place, the limitation function may not operate as intended.

Each time the C-HR slows without the friction brakes, the motors run as generators and send current back to the pack. In low temperatures, with the state of charge already high and the car staying in regenerative mode for a long stretch, such as coasting several miles downhill, the pack can be driven past its limit.

Toyota describes the result: warning lights illuminate and a warning buzzer sounds, indicating that the electric drive system has shut down. The filing places the hazard at higher speeds, where a car that stops making power becomes an obstacle to the traffic behind it. The report does not address whether power steering or brake assist continue after the shutdown.

The ECU is a Denso Corporation part from Kariya, Japan, listed on the filing as "Computer ASSY, Hybrid Vehicle Control" under part numbers 89980-42G40 and 89980-42G50. Denso also supplied the battery ECU behind campaign 26V393, the June 2026 loss-of-drive-power recall on the Toyota bZ, Lexus RZ and Subaru Solterra. That campaign traced to two integrated circuits overwriting each other's memory inside the module rather than to a charging parameter, and the C-HR is not part of it.

Affected Models

Model	Model year	Production dates	Units
Toyota C-HR (battery electric)	2026	Feb 6, 2026 - Jul 10, 2026	8,521

Not every car built in that window was sold in the United States, and the population is defined by the ECU software rather than the build date. Toyota states that other Toyota and Lexus vehicles sold here either have no BEV ECU or run different software on theirs, so the campaign does not reach the bZ, the Lexus RZ or any hybrid.

Toyota's dealer notice gives a wider production window, late October 2025 to mid-July 2026, than the February 6 start date on the federal filing. The Part 573 is the population record, and the VIN lookup settles any individual car.

The same dealer notice counts about 2,550 of the 8,521 in new dealer inventory as of August 2026, and it opens with a stop-sale instruction: no new C-HR covered by the campaign can be delivered under sale or lease until the software update is done. Toyota is reimbursing dealers for flooring costs on those cars until the recall remedy becomes available.

Chronology and Investigation

In late April 2026, Toyota's development engineers found an incorrect software parameter in the BEV ECU of a future battery-electric model. The company then went back through the BEV ECU parameters on the electric models already in the market and found an incorrect parameter in the C-HR, in the value used for battery charging control.

Between April and June, Toyota worked out what the wrong value could do and formed the working hypothesis: the charging limitation function might not operate as intended, letting the battery overcharge at a high state of charge and shutting the drive system down while driving.

In July 2026, Toyota ran vehicle bench and simulation tests combining regenerative braking, high battery state of charge, a range of temperatures and different vehicle speeds. The drive system could shut down from overcharging when regenerative braking was applied over long distances, and the effect was strongest in low temperatures with the battery near full.

On August 28, 2026, Toyota decided on a voluntary safety recall. The Part 573 reached NHTSA on September 2, the same day dealers were notified. No NHTSA investigation preceded the filing, and Toyota lists no related campaign number.

Reported Incidents

As of August 26, 2026, Toyota reports no Field Technical Reports and no warranty claims from U.S. sources related to the condition. The Part 573 does not state a crash, injury or fatality count.

The oldest cars in the population were built in February 2026, per the Part 573, and have seen little or no winter driving. Toyota found the shutdown on a test bench, and the filing does not claim the fault has occurred on a customer's car.

Remedy and Notification

The remedy is a BEV ECU software update performed by a Toyota dealer at no charge. The filing lists it as a software remedy with no do-not-drive and no park-outside advisory. It is not an over-the-air update; the car has to go to a dealer.

Dealers were notified September 2, 2026. Toyota's dealer bulletin says notifications will appear on the car's head unit starting in late October 2026, and that affected vehicles show in the Toyota app from the date of announcement. Owner letters are scheduled to mail between October 18 and November 1, 2026, as a phased recall, with no interim letter ahead of them.

The Part 573 leaves the date VINs become searchable on NHTSA.gov blank. Toyota's customer line is 1-800-331-4331; the dealer bulletin routes questions to the Toyota Brand Engagement Center at 1-888-270-9371. The recall number to quote is 26TA17.

Toyota's dealer FAQ carries one piece of interim advice: until the update is performed, charging to an 80 percent state of charge can help avoid overcharging during regenerative braking.

Symptoms to Watch For

The Part 573 leaves the "identification of any warning that can occur" field blank, but the defect description names the sequence.

Warning lights and a buzzer together. Toyota's filing describes warning lights illuminating with a warning buzzer, and states that this indicates the electric drive system has shut down.

Loss of motive power at speed. The car stops responding to the accelerator. Because the filing is silent on steering and brake assist, treat the event as a controlled coast to the shoulder.

A full battery on a cold morning before a long descent. This is the set of conditions Toyota reproduced in testing rather than a symptom, and it is the one an owner can see coming. A car charged to 100 percent overnight in low temperatures, leaving from the top of a grade, is in the scenario the filing describes.

Regenerative braking behaving normally right up to the shutdown. Nothing in the filing suggests the car reduces regeneration on its own or warns as the pack approaches its limit.

Drive mode reset to Normal after the dealer visit. The reflash returns the drive mode setting to Normal and clears learned energy-consumption values, and Toyota tells dealers to explain that to the customer.

How Long Will the Recall Repair Take?

Toyota pays dealers 0.8 flat-rate hours for operation code 26TA17R1, which includes 0.1 hours of administrative time, and its owner FAQ puts the repair at approximately 45 minutes. The work is an in-car reflash: the technician runs a health check with the GTS+ scan tool, checks the current calibration ID against Toyota's table, and loads one of two 11-megabyte calibration files while a DCA-8000 power supply holds the 12-volt auxiliary battery steady.

Toyota's technical instructions warn that a voltage drop on the car or the laptop during the flash can damage the BEV ECU, and that the company will not reimburse dealers for reprogramming failures. Technicians must have completed the TIC209A Electrified Vehicle Repair course to do the job.

There are no parts to order, so scheduling rather than supply sets the wait. Dealers also have about 2,550 unsold cars to flash before they can deliver them, and those cars share the same trained technicians with customer appointments through the fall.

Bottom Line

A drive system that quits at highway speed is the serious end of software recalls, and this one has a narrow trigger: cold weather, a battery near full, and a long stretch of regeneration without the motors ever drawing the pack back down. An owner who plugs in to 100 percent every night at the top of a mountain pass in January matches the conditions the filing describes. An owner charging to 80 percent in a flat, warm city is far from them.

Until the letter arrives, set the charge limit to 80 percent, which is Toyota's own interim advice. If the warning lights and buzzer come on together, get the car to the shoulder and stop.

Dealers have had the calibration since September 2, 2026, so a call quoting 26TA17 books the 45-minute flash without waiting for the letter.

Find your Toyota C-HR recall information: https://www.toyota.com/recall/