Toyota bulletin T-SB-0021-25
Toyota filed this with NHTSA as a service bulletin dated Feb 10, 2025, received Mar 11, 2025, about the engine — 2 documents under this number. It names 60 model years (2021–2025). A service bulletin is not a safety recall: it is the manufacturer telling its dealers how to diagnose or repair a condition, and whether the work is paid for depends on the warranty in force. Quoting the number at a service desk can save a diagnosis.
What the bulletin says
Source: NHTSA's summary of the manufacturer's communicationFlash reprogramming allows the Electronic Control Unit (ECU) software to be updated without replacing the ECU. Flash calibration updates for specific vehicle models/ECUs are released as field-fix procedures described in individual Service Bulletins. This bulletin details the Global Techstream+ (GTS+) ECU flash reprogramming procedures and outlines use of the Technical Information System (TIS) and the Calibration Update Wizard+ (CUW+). To ensure the correct ECU software is installed, ECUs will require a Security Signature before the ECU will initialize the flash reprogramming sequence. This bulletin also details the process for acquiring a Security Signature from TIS during the GTS+ ECU flash reprogramming process.
Documents filed under this number
| Document | Kind | Dated | NHTSA id | At NHTSA |
|---|---|---|---|---|
| T-SB-0021-25 | Service bulletin | Feb 10, 2025 | 11016782 | not yet checked |
| T-SB-0021-25 | Service bulletin | Feb 10, 2025 | 11015496 | not yet checked |
The summary is NHTSA’s abstract of the document, as filed under 49 CFR 579.5. One communication is usually filed as several documents — the bulletin, a dealer notice, an owner letter — and the number on any of them finds this page. A PDF link is shown only once NHTSA’s own server has been seen to serve that document; the rest are checked over the following nights. Quote the number at a service desk; it is what the dealer’s system is keyed on.
Model years it names
Source: as the manufacturer filed themand 14 more model years on this site.
Also filed against model years this site has no page for: 2022 Toyota Redundant 86; 2023 Toyota Redundant 86; 2024 Toyota Redundant 86; 2025 Toyota Redundant 86; 2024 Toyota Redundant Land Cruiser; 2025 Toyota Venza Hybrid.
A vehicle page’s bulletin list shows the newest few communications filed against that model year; the count there is every one.
Common questions
Source: NHTSA, 49 CFR 579.5Is Toyota T-SB-0021-25 a recall?
No. A service bulletin is a manufacturer communication filed with NHTSA under 49 CFR 579.5; a safety recall carries an NHTSA campaign number (two digits, a letter, six digits) and a federal duty to repair for free. Check the vehicle’s recalls by VIN at nhtsa.gov/recalls, or on its page here.
Is the T-SB-0021-25 repair free?
Not automatically. A service bulletin describes how to diagnose or repair a condition; who pays depends on the warranty in force, any extension, and the dealer. Quoting the number can save a diagnosis either way.
Which vehicles does T-SB-0021-25 cover?
The manufacturer filed it against 60 model years: 2025 Toyota 4Runner, 2025 Toyota Corolla, 2024 Toyota Corolla, 2023 Toyota Corolla, 2025 Toyota Corolla Cross, 2024 Toyota Corolla Cross and more. Whether one particular vehicle is affected is a matter of its VIN and its build, not its model year alone.