Check a VIN

February 10, 2025 Service bulletin

Flash reprogramming allows the Electronic Control Unit (ECU) software to be updated without replacing the...

Toyota technical service bulletin T-SB-0021-25 for 2023-2025 Toyota Prius, 2023-2025 Toyota Corolla and 2024-2025 Toyota Tacoma and others.

Bulletin number
T-SB-0021-25 (T-SB-0021-25)
Component
Engine
Summary
Flash 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.

Owners of these vehicles have filed 942 complaints in the engine category.

Vehicles covered

VIN decoder

See the problems and recalls for an exact car

Buying a used Toyota Prius?

Check the exact car before you pay: accidents, salvage or flood titles, odometer readings and previous owners.

Check its history