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Service bulletins for the 2025 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.

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

About U1174 on the 2025 Toyota Sienna: what the code means, and the bulletins and recalls about the same components.

By type

By component

By trouble code

Only bulletins with trouble code: U1174 are shown. Show all

Bulletins, newest first
T-SB-0035-25 Rev12025-08-08. Service bulletin. UNKNOWN OR OTHER. Some 2025 model year Sienna Hybrid vehicles equipped with the advanced rear seat reminder system may exhibit one or both of the following conditions: •A “Rear Seat Reminder Malfunction – Visit Your Dealer” message on the Multi-information Display (MID). •Diagnostic Trouble Code (DTC) U117487 (Lost Communication with Cabin Occupant Recognition Sensor Missing) present in the main body ECU. The cabin object recognition sensor assembly logic has been modified to address these conditions.
T-SB-0035-252025-06-06. Service bulletin. STRUCTURE:BODY. Some 2025 model year Sienna Hybrid vehicles equipped with the advanced rear seat reminder system may exhibit one or both of the following conditions: • A “Rear Seat Reminder Malfunction – Visit Your Dealer” message on the Multi-information Display (MID). • Diagnostic Trouble Code (DTC) U117487 (Lost Communication with Cabin Occupant Recognition Sensor Missing) present in the main body ECU. The cabin object recognition sensor assembly logic has been modified to address these conditions.
T-SB-0035-252025-05-15. Service bulletin. STRUCTURE:BODY. Some 2025 model year Sienna Hybrid vehicles equipped with the advanced rear seat reminder system may exhibit one or both of the following conditions: • A “Rear Seat Reminder Malfunction – Visit Your Dealer” message on the Multi-information Display (MID). • Diagnostic Trouble Code (DTC) U117487 (Lost Communication with Cabin Occupant Recognition Sensor Missing) present in the main body ECU. The cabin object recognition sensor assembly logic has been modified to address these conditions.

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