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Service bulletins for the 2021 Toyota Sienna

A bulletin is a manufacturer's communication to its dealers, as NHTSA indexes it. The summary is NHTSA's. The document is the manufacturer's: read it at NHTSA. A bulletin is not a recall, and listing a model year does not mean every vehicle of it is concerned.

176 on file from NHTSA, as of 2026-10-19.

By type

By component

By trouble code

Only bulletins with component: Engine are shown. Show all

Bulletins, newest first
T-SB-0110-20 Rev22026-09-09. Service bulletin. ENGINE. OBSOLETE NOTICE August 20, 2026: This bulletin is now obsolete. Please see T-SB-0051-26.
T-SB-0051-262026-09-09. Service bulletin. ENGINE. This bulletin includes basic procedures for performing a rescue charge at battery on high voltage (HV) Ni-MH and Li-ion batteries.
24TE042026-09-09. Warranty extension. ENGINE. Although the flow shut-off valve is covered by Toyota’s New Vehicle Limited Warranty for 36 months or 36,000 miles (whichever comes first), we at Toyota care about the customers’ ownership experience. Toyota is providing coverage for repairs related to Flow Shut-off Valve Coolant Leak.
T-SB-0104-21 Rev22026-03-07. Service bulletin. ENGINE. OBSOLETE NOTICE February 27, 2026: This bulletin is no longer applicable and is now obsolete.
24TE042025-09-09. Service campaign. ENGINE. The specific condition covered by this program is for a small engine coolant leak that can occur from the flow shut-off valve that can allow coolant to drip on other parts of the vehicle. This can cause "Engine Maintenance Required" to be displayed on the instrument cluster or cause the A/C not to function normally. Although the flow shut-off valve is covered by Toyota’s New Vehicle Limited Warranty for 36 months or 36,000 miles (whichever comes first), we at Toyota care about the customers’ ownership experience. Toyota is providing coverage for repairs related to Flow Shut-off Valve Coolant Leak.
T-SB-0112-24 Rev22025-07-10. Service bulletin. ENGINE. Some 2018 – 2021 model year Toyota vehicles equipped with an A25A-FKS, A25A-FXS, or M20A-FKS engine may exhibit a condition in which an “Engine Maintenance Required” message is displayed in the Multi-Information Display (MID). Additionally, the vehicle will exhibit DTC(s) P268111 (Engine Coolant Bypass Valve Circuit Short to Ground) and/or P268115 (Engine Coolant Bypass Valve Circuit Short to Battery or Open).
24TE042025-04-08. Warranty extension. ENGINE. Although the flow shut-off valve is covered by Toyota’s New Vehicle Limited Warranty for 36 months or 36,000 miles (whichever comes first), we at Toyota care about the customers’ ownership experience. Toyota is providing coverage for repairs related to Flow Shut-off Valve Coolant Leak.
T-SB-0021-252025-04-08. Service bulletin. ENGINE. 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.
T-SB-0107-20 Rev22025-03-25. Service bulletin. ENGINE. OBSOLETE NOTICE February 11, 2025: This bulletin is now obsolete. Please see T-SB-0021-25.
24TE042025-03-11. Warranty extension. ENGINE. Although the flow shut-off valve is covered by Toyota’s New Vehicle Limited Warranty for 36 months or 36,000 miles (whichever comes first), we at Toyota care about the customers’ ownership experience. Toyota is providing coverage for repairs related to Flow Shut-off Valve Coolant Leak.
T-SB-0021-252025-03-11. Service bulletin. ENGINE. 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.
T-TT-0771-252025-02-12. Service bulletin. ENGINE. Some 2021-2025 MY Highlander HV, Sienna HV, RAV4, and RAV4 HV, may exhibit an oil leak from the area where the camshaft cover, camshaft housing, and the timing chain covers meet. This is typically seen on the exhaust side of the engine.
T-SB-0112-24 Rev12025-02-12. Service bulletin. ENGINE. Some 2018 – 2021 model year Toyota vehicles equipped with an A25A-FKS, A25A-FXS, or M20A-FKS engine may exhibit a condition in which an “Engine Maintenance Required” message is displayed in the Multi-Information Display (MID). Additionally, the vehicle will exhibit DTC(s) P268111 (Engine Coolant Bypass Valve Circuit Short to Ground) and/or P268115 (Engine Coolant Bypass Valve Circuit Short to Battery or Open).
T-SB-0110-20 Rev22025-01-09. Service bulletin. ENGINE. This bulletin includes basic procedures for performing a rescue charge at battery on high voltage (HV) Ni-MH and Li-ion batteries. This bulletin should be used in conjunction with the applicable model and model year Repair Manual while performing the battery rescue charge. The GRX-5100 should be used wherever the Repair Manual references the Toyota Hybrid System (THS) charger.
24TE042025-01-09. Warranty extension. ENGINE. CUSTOMER SUPPORT PROGRAM 24TE04 Multiple Model & Model Year Toyota Vehicles Coverage for Flow Shut-off Valve Coolant Leak Frequently Asked Questions
24TE042025-01-09. Warranty extension. ENGINE. Although the flow shut-off valve is covered by Toyota’s New Vehicle Limited Warranty for 36 months or 36,000 miles (whichever comes first), we at Toyota care about the customers’ ownership experience. Toyota is providing coverage for repairs related to Flow Shut-off Valve Coolant Leak.
24TE042025-01-09. Warranty extension. ENGINE. Although the flow shut-off valve is covered by Toyota’s New Vehicle Limited Warranty for 36 months or 36,000 miles (whichever comes first), we at Toyota care about the customers’ ownership experience. Toyota is providing coverage for repairs related to Flow Shut-off Valve Coolant Leak.
24TE042025-01-09. Warranty extension. ENGINE. In our continuing efforts to ensure the best in customer satisfaction, Toyota is announcing a Customer Support Program to provide coverage for Flow Shut-off Valve Coolant Leak on multiple Model & Model Year Toyota Vehicles. Although the flow shut-off valve is covered by Toyota’s New Vehicle Limited Warranty for 36 months or 36,000 miles (whichever comes first), we at Toyota care about the customers’ ownership experience. Toyota is providing coverage for repairs related to Flow Shut-off Valve Coolant Leak.
T-SB-0112-242025-01-09. Service bulletin. ENGINE. Some 2018 – 2021 model year Toyota vehicles equipped with an A25A-FKS, A25A-FXS, or M20A-FKS engine may exhibit a condition in which an “Engine Maintenance Required” message is displayed in the Multi-Information Display (MID). Additionally, the vehicle will exhibit DTC(s) P268111 (Engine Coolant Bypass Valve Circuit Short to Ground) and/or P268115 (Engine Coolant Bypass Valve Circuit Short to Battery or Open).
24TE042025-01-09. Warranty extension. ENGINE. This Customer Support Program provides coverage as it applies to Flow Shut-off Valve Coolant Leak on Certain 2019-2021 Avalon & Avalon HV, 2018-2021 Camry & Camry HV, Certain 2020-2021 Corolla, Certain 2019-2021 Corolla HB, 2020-2021 Highlander, Certain 2019-2021 RAV4 & RAV4 HV, Certain 2021 RAV4 PHV, Certain 2021 Sienna HV, Certain 2021 Venza vehicles. The specific condition covered by this program is a small engine coolant leak can occur from a specific valve that can allow coolant to drip on other parts of the vehicle. This can cause "Maintenance Required" to be displayed on the instrument cluster or cause the A/C not to function normally. If the condition is verified, the vehicle will be repaired with a new Flow Shut-off Valve under the terms of this Customer Support Program
24TE042025-01-09. Warranty extension. ENGINE. Frequently Asked Questions CUSTOMER SUPPORT PROGRAM 24TE04 Multiple Model & Model Year Toyota Vehicles Coverage for Flow Shut-off Valve Coolant Leak
24TE042025-01-09. Warranty extension. ENGINE. Although the flow shut-off valve is covered by Toyota’s New Vehicle Limited Warranty for 36 months or 36,000 miles (whichever comes first), we at Toyota care about the customers’ ownership experience. Toyota is providing coverage for repairs related to Flow Shut-off Valve Coolant Leak.
T-SB-0103-20 Rev12024-07-23. Service bulletin. ENGINE. This Service Bulletin provides updated non-electric water pump leak inspection and diagnostic tips for some 2008 – 2025 model year Toyota vehicles.
T-TT-0694-22 Rev22024-07-23. Service bulletin. ENGINE. After jump-starting, the vehicle may experience a no-start condition and multiple DTCs including U010087. Upon investigation, it is found that the engine ECU has been damaged and needs to be replaced. In several cases, it was found that the cause of the ECU damage was improper jump starting. Further investigation found that ECU damage may occur if the negative (ground) cable clamps are attached on or around the engine ECU or ECU mounting bracket.
T-SB-0103-20 Rev12024-07-23. Service bulletin. ENGINE. This Service Bulletin provides updated non-electric water pump leak inspection and diagnostic tips for some 2008 – 2025 model year Toyota vehicles.

The summaries are NHTSA's. Each bulletin's page links NHTSA's copy of the manufacturer's document.