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Service bulletins for the 2012 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.

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

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Only bulletins with component: Electrical system are shown. Show all

Bulletins, newest first
T-TT-307-14 Rev12017-08-14. Service bulletin. EQUIPMENT:ELECTRICAL; ELECTRICAL SYSTEM:SOFTWARE; EQUIPMENT:ELECTRICAL:NAVIGATIONAL SYSTEM(GLOBAL POSITIONING SYSTEM); EQUIPMENT:ELECTRICAL:RADIO/TAPE DECK/CD ETC.. TT: Customers complain of various Bluetooth connectivity concerns after upgrading to iOS 8.0 and later. Conditions typically experienced include inability to pair the iPhone to the system, poor sound quality during phone calls placed through the audio/navigation system, and the inability to place a hands free phone call using the audio/navigation system.
T-TT-0337-152017-08-14. Service bulletin. EQUIPMENT:ELECTRICAL:NAVIGATIONAL SYSTEM(GLOBAL POSITIONING SYSTEM); ELECTRICAL SYSTEM:SOFTWARE; EQUIPMENT:ELECTRICAL:RADIO/TAPE DECK/CD ETC.. TT: When updating either the navigation or radio firmware, verify the vehicle applicability BEFORE beginning the update.
T-SB-0101-11 Rev2017-08-14. Service bulletin. EQUIPMENT:ELECTRICAL; ELECTRICAL SYSTEM. TSB: When servicing interior electrical switches and components, please note the precautions in this bulletin to avoid damaging electrical components and switches. Many lubricants, cleaners, and automotive chemicals contain silicone or other compounds that may contaminate electrical contacts, and therefore increase electrical resistance and decrease switch performance. The use of any cleaners or fluids may increase the risk of further damage to electrical components.
T-TT-0307-142017-08-01. Service bulletin. ELECTRICAL SYSTEM:SOFTWARE; EQUIPMENT:ELECTRICAL:RADIO/TAPE DECK/CD ETC.; EQUIPMENT:ELECTRICAL:NAVIGATIONAL SYSTEM(GLOBAL POSITIONING SYSTEM). Tech Tip: Customer complains of carious Bluetooth connectivity concerns after upgrading to iOS 8.0 and later. Conditions typically experienced include inability to pair the iPhone to the system, poor sound quality during phone calls placed through the audio/navigation system, and the inability to place a hands free phone call using the audio/navigation system.
T-TT-0362-152017-03-28. Service bulletin. ELECTRICAL SYSTEM; ENGINE. TT: THE VEHICLE MAY BE DIFFICULT TO START OR HAVE AN ABNORMALLY LOW OR ROUGH IDLE AFTER THE BATTERY HAS BEEN DISCONNECTED OR POWER TO THE ENGINE ECM HAS BEEN INTERRUPTED.
T-SB-0012-13 REV2017-03-21. Service bulletin. ENGINE; ELECTRICAL SYSTEM. "TSB: FLASH REPROGRAMMING ALLOWS THE 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 TECHSTREAM ECU FLASH REPROGRAMMING PROCESS AND OUTLINES USE OF THE TECHNICAL INFORMATION SYSTEM (TIS) AND THE CALIBRATION UPDATE WIZARD (CUW). FLASH CALIBRATION UPDATES CAN ONLY BE APPLIED TO THE VEHICLE/ECU COMBINATION FOR WHICH THEY ARE INTENDED. ECUS HAVE INTERNAL SECURITY THAT WILL NOT ALLOW THEM TO BE PROGRAMMED WITH ANOTHER ECU’S INFORMATION."
T-SB-0035-132016-04-12. Service bulletin. ELECTRICAL SYSTEM. SUMMARY TO BE PROVIDED ON A FUTURE DATE.
T-SB-0055-122012-05-16. Service bulletin. ENGINE AND ENGINE COOLING:ENGINE:GASOLINE:BELTS AND ASSOCIATED PULLEYS; ELECTRICAL SYSTEM:ALTERNATOR/GENERATOR/REGULATOR. TOYOTA: CHARGING SYSTEM INOPERATIVE. SOME ENGINES MAY EXHIBIT INSUFFICIENT CHARGING PERFORMANCE FROM THE ALTERNATOR. AN UPDATED PULLEY ASSEMBLY IS AVAILABLE TO ADDRESS THIS CONDITION. *JS

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