2026 Toyota Bz

SUPPLEMENT TO ODI COMPLAINT 11758090 (filed 8/19/2026). Two corrections, an identified component, and a verified manufacturer remedy. Full narrative attached. CORRECTIONS. (1) The prior 12V battery was replaced 5/29/2026, not June 2026; invoice 569207 is correct. (2) The complaint attributed the drain to an armed charging schedule. That was a proxy, not the cause. The trigger is ANY vehicle wake -- key-fob approach at ~8 ft, end of drive, or converter pulse -- which arms a timer of exactly 180 minutes, after which a 0.87-0.9 A sawtooth discharge runs 4.6-9 hours, consuming up to 12 Ah. Verified 8 of 8 events 8/8-8/23/2026 by amp-hour shunt and independent voltage logger, one pre-registered in advance and correct to the minute. The defect is not avoidable by any owner setting. REMEDY. 8/24/2026, Cavender Toyota, repair order 604263, under Toyota Technical Assistance System case TA262360433: ignition off; vehicle removed from owner's Toyota app garage; ignition on 1 min (pending telematics upload completes); off 1 min; on; vehicle re-added to app garage. No parts, no charge, ~10 minutes. The procedure operates only on the DCM/connected-services registration state, which identifies the component. VERIFICATION. Two deliberate fob wakes 8/24 (19:25, 23:10 CDT): no discharge at 180 minutes or overnight. Twelve days of normal use through 9/5/2026: zero events. TOYOTA'S OWN RECORDS CORROBORATE. The TAS advisory tells the technician to "set up for 3 hours to monitor," matching the measured 180-minute latency. Invoice 593644 records the 12V battery needing 2.5 hours of external charging. The TAS case records "Dealer Visit: 4," escalation reason "Multiple Repair." The dealer's 8-day monitoring (7/28-8/5) found nothing because a vehicle parked in a service lot is never woken: 1 mile accrued in 8 days. No recall or TSB communicates this remedy; case TA262360433 remains open, "Vehicle Repaired" blank. Full instrumented record available to ODI on request.

NHTSA ID

11762359

Incident

May 16, 2026

The 12-volt auxiliary battery system repeatedly discharges itself and has twice left the vehicle completely inoperative: 7/24/2026 (5.58 V at the battery, parked unplugged ~46 hours after the last drive) and 7/28/2026 (5.95 V, failure during an attempt to enter READY to drive). The 12V system controls the contactors connecting the high-voltage traction battery to the drive system; when it collapses the vehicle cannot be started or driven even though the traction pack holds charge. The dealer replaced the 12V battery under warranty in June 2026; failures continued, so the battery was not the cause. I instrumented the 12V system with two independent cross-validated meters (precision current/amp-hour shunt; voltage logger sampling every 2 minutes) and measured the mechanism over 12 continuous days (Aug 8-19, 2026). Findings: (1) A drain event begins exactly 3 hours (180 min, within one 2-minute sample, in all six measured events) after the most recent vehicle wake - a READY cycle or the key fob merely coming within detection range of the parked car. Each new wake restarts the 3-hour countdown. (2) The event draws ~0.87 A; four completed events ran 4.6-4.7 hours (~4 Ah each), one ran 9.2 hours (~8 Ah). (3) Events occur with all charging schedules verified off in both vehicle and phone app, the app closed, and the vehicle unplugged. (4) The vehicle never replenishes the 12V from the traction pack while parked, and undercharges it when driven (13.9 V ceiling, single 30-minute window). Ordinary daily use - driving, parking unplugged, or walking near the car with the fob - drains the battery to collapse within days. No owner setting prevents it. A 6-day dealer observation did not reproduce it because the vehicle sat undisturbed: no wake, no drain. No warning lamps preceded either failure. Instrumented logs attached; vehicle and data available for inspection on request.

NHTSA ID

11758090

Incident

Jul 28, 2026

The 12 volt battery exhibits a consistent parasitic drain. This is intermittent, but results in the vehicle failing to start. The failure to start is an issue because it is happening frequently and could endanger individuals who live in rural areas or areas with cold or hot climate. This issue has happened to us multiple times and Toyota has not recalled or provided guidance to its dealer service network. Many effected owners have a diagnostic data backed theory that links the drain on the 12 volt battery to Toyota digital communication module. That diagnostic can be found here. Toyota should be forced to investigate and fix this as it is a big safety concern for those who are in rural harsh climates! It is impacting a lot of new BZ & CHR owners, but has been a known issue with previous models and even covered by some media outlets. Because this is a parasitic drain there often isnt a low battery warning before the car won't start. Another reason this deserves attention.

NHTSA ID

11756337

Incident

Jul 30, 2026

There is a foul smell emanating from the window areas of the vehicle after rain. The more rain, the more pronounced the odor. It smells similar to cat urine. I have been able to reproduce it many times, after it rains. I was reading online that the smell is caused by mold/mildew which is a huge safety concern. I had also read that this is somewhat of a common issue caused by the type of weatherstripping in use on the vehicle. When I called the dealership they were unaware of any issues concerning an odor around the windows after rain. I will continue to work with the dealership, but this should at least be a Technical Service Bulletin.

NHTSA ID

11755648

Incident

Aug 8, 2026

The vehicle suffers from an overnight parasitic 12V battery drain caused by a continuous cloud activation/software communication loop involving the Data Communication Module (DCM) and telematics system. The vehicle has gone completely dead and required jumping on three separate occasions. The issue was inspected and documented on a service invoice by an authorized dealership, which confirmed the battery itself tested good and recommended disconnecting the mobile application link due to the DCM cloud activation causing battery depletion. The recurring dead 12V battery creates a safety hazard by leaving the vehicle completely inoperable and stranded without warning.

NHTSA ID

11755120

Incident

Aug 5, 2026

Vehicle experienced a catastrophic, terminal 12V auxiliary battery parasitic drain that flatlines the system to 0% while parked, creating a severe safety risk by stripping hazard lights and motive power. This is the 3rd identical electrical collapse within 4 weeks; a late June 12V battery replacement failed. The vehicle was in active daily use, not stored.Held out of service at Kings Toyota since July 6, 2026 (26+ days down). Technicians dismantled the cabin and placed the dashboard in the trunk to trace loops. Management confirmed hardware nonconformities in the Data Communication Module (DCM) and Body Control Module (BCM), which fail to enter sleep mode. Observable proof includes continuous, erroneous telemetry alerts stating windows are down/doors unlocked while fully locked and disassembled in the bay.Modules are on indefinite global backorder due to an inherent manufacturing defect. Parts are restricted likely to feed production and the mass rollout for NHTSA Campaign 26V393.DIAGNOSTIC DETAILS:Local tech efforts are directly guided by Toyota Corporate factory engineers who designed the vehicle, as local techs have never encountered this severe issue.Multiple other identical units are grounded on the dealer lot with identical 12V flatline failures.My vehicle (#XXX) is being used instructively by Toyota Corporate to advance understanding and map out repairs for the other units.To capture evading data, I complied with a request to delete the Toyota app from my iPhone so lead tech [XXX] could intercept these failing module notifications to aid factory engineers.Management confirmed that by design, if the 12V drops below 11V, the high-voltage motive battery is supposed to automatically recharge it. Here, the vehicle fails to initiate the loop, or the motive batteries enter a defensive "protective lockout mode," cutting power transfer and flatlining the car. This could contribute to motive battery failure /lockout if the defect continues to draw 12V battery down. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INF

NHTSA ID

11752772

Incident

Jun 13, 2026

Vehicle purchased late March. Since then, the 12V gets completely drained to 0% over the weekend. This is a biweekly problem. Vehicle taken to dealership, they were not able to replicate problem. Dealership claims battery and vehicle perfectly fine. 12V battery continues to get discharged. This issue puts the customer at risk of being stranded on trips. No warning lamps or symptoms before battery dies making vehicle completely inoperable. Research online and owner forums clearly show a large number of owners having the same issue with this defect with this vehicle. Contacted toyota and they denied vehicle glitch or resolution. Toyota instructed me to take car back to dealership for them to address.

NHTSA ID

11751814

Incident

Jul 19, 2026

I am writing to formally report an unsafe design feature regarding the automatic headlight cleaner/washer system on the 2026 Toyota bZ.The vehicle is programmed to automatically spray windshield washer fluid onto the headlights when the headlights are active and the windshield washer lever is pulled. As a night-shift worker, I frequently operate this vehicle in complete darkness. When the high-pressure fluid sprays over the active headlight lenses, it immediately diffuses the light beam. This causes the forward headlights to dim drastically, rendering them almost completely unusable for several seconds until the water clears.This sudden, unprompted loss of forward visibility at highway speeds creates an immediate and severe driving hazard.Proposed Remedy Request:There is currently no setting available to the driver to turn off or modify this linked behavior. I request that Toyota issue a software update allowing owners an menu option to disable the automatic, windshield-linked headlight washing function so drivers can maintain constant headlight visibility at night.

NHTSA ID

11751216

Incident

Jul 17, 2026

State of Health (SOH): An estimate of battery health that is updated as the vehicle learns from operating and charging conditions over time. Distance Since Last Update: Indicates the distance accumulated since the last SOH calculation. A default mileage value of 40,727 at SOH 100% may be displayed until sufficient vehicle learning is completed. Once SOH value updates from 100%, the Distance Since Last Update value will re-set to 0 miles. Both SOH and Distance Since Last Update values will continue to update as the vehicle continues to learn.

Some 2026 model year bZ, bZ Woodland, and C-HR BEV vehicles may exhibit the Diagnostic Trouble Code (DTC) U255221F associated with the level 3 DC fast charging. Under certain conditions, charging may either operate normally or experience failure, with a charging malfunction message displayed on the Multi-Information Display (MID). This condition is attributed to a control logic issue and potential voltage drop affecting Plug-In Charge Control Computer Assembly functionality. The control logic has been modified to reduce the possibility of this condition.

2026 model year Toyota vehicles are equipped with driver side floor mat retainers to secure the floor mat in the correct position. In addition, some models may also utilize retainers for passenger side and rear seat floor mats. During Pre-Delivery Service (PDS), follow the appropriate Installation Procedure to attach the driver side, and if applicable, the passenger side and rear seatfloor mats to the vehicle carpet using the floor mat retainers.

During the manufacturing process, tires are mounted on the vehicle as matched sets to help reduce conditions such as pulling or drifting. If the wheels are replaced or refinished before vehicle delivery, it is important that the tires remain on the vehicle in the same location and in the same direction of rotation.

Long-term or off-site storage requires special care to maintain vehicle condition. The following guidelines should be performed to minimize vehicle component/part degradation due to extendedvehicle storage conditions. Long-term storage can affect a vehicle’s systems and components. Any problems that are found should be corrected immediately.

A battery in a stored vehicle is subject to conditions that can reduce its performance and service life. These conditions include storage period, temperature, parasitic drain, and battery load. Because of these factors, battery inspection and maintenance are required in order to ensure proper operation and optimal battery life.