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Service bulletins for the 2020 Toyota Sequoia

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.

143 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-SB-0009-19_Rev2020-04-13. Service bulletin. EQUIPMENT; SERVICE BRAKES; ELECTRICAL SYSTEM. TSB: Long-term or off-site storage requires special care to keep vehicles factory fresh and ready for delivery. The following guidelines should be performed to minimize vehicle component/part degradation due to extended vehicle storage conditions. Long-term storage can affect a vehicle?s systems and components. Any problems that are found should be corrected immediately.
T-SB-0008-19_Rev2020-04-13. Service bulletin. ELECTRICAL SYSTEM; EQUIPMENT. TSB: An initialization procedure is required to activate the Entune? 3.0 App Suite Connect for Audio, Audio Plus, and Premium Audio head units before they are used for the first time on new vehicles. The initialization procedure may also be performed under other circumstances, such as following a head unit replacement or after the customer?s personal settings are erased. The initialization procedure requires between 3 and 15 minutes to complete, depending on file size, cellular connection speed, and other factors. Following the initialization procedure, individual Entune? 3.0 apps may periodically update through an over-the-air update system. Updates are optional or mandatory. The update procedure will take approximately 1 minute for each app requiring an update. Follow the Initialization/Update Procedure in this bulletin to perform the initialization and app updates.
T-TT-0588-19_Rev2020-03-30. Service bulletin. ELECTRICAL SYSTEM; EQUIPMENT. TT: Some 2020 model year vehicles may display abnormal Safety Connect operation during PDS or after replacement due to DCM activation issues. If there are no DTCs present and after the initial SOS light flashing sequence after ignition on, neither the red nor green light stays on in the overhead console determine if the vehicle is in shipping mode. To determine if a vehicle is experiencing this condition, connect a Techstream and navigate to: Telematics-Data List - ?Telematics Activation Status?. If this value is displayed as ?Shipping?, continue to the Shipping Mode recommendations below, and do not create a TAS case.
T-TT-0588-19_Rev2020-03-30. Service bulletin. EQUIPMENT; ELECTRICAL SYSTEM. TT: Some 2020 model year vehicles may display abnormal Safety Connect operation during PDS or after replacement due to DCM activation issues. If there are no DTCs present and after the initial SOS light flashing sequence after ignition on, neither the red nor green light stays on in the overhead console determine if the vehicle is in shipping mode. To determine if a vehicle is experiencing this condition, connect a Techstream and navigate to: Telematics-Data List - ?Telematics Activation Status?. If this value is displayed as "Shipping", continue to the Shipping Mode recommendations below, and do not create a TAS case.
T-SB-0093-19_Rev2020-03-30. Service bulletin. ELECTRICAL SYSTEM; STRUCTURE. TSB: Pre-Delivery Service (PDS) is a critical step in satisfying our dealership?s new car customers. Customer feedback indicates the following areas deserve special attention when performing PDS: ?Careful inspection for paint chips/scratches and body dents/dings. ?Proper operation of electrical accessories. ?Interior cleanliness. ?Proper function of mechanical systems. Customer retention and proper maintenance of vehicles are and have always been a major focus for Toyota. To help remind customers that regular service is essential to the proper maintenance of the vehicle, dealers are required to install a service reminder sticker before delivery. By doing this, customers will be reminded to return to your dealership for service. Your current service reminder sticker may be used. (See PDS Check Sheet ?Final Inspection and Cleaning.?) A new PDS Check Sheet has been developed for the 2020 model year Sequoia. Some check points have been added, expanded, or clarified.
T-TT-0588-192020-02-24. Service bulletin. EQUIPMENT; ELECTRICAL SYSTEM. TT: Some 2020 model year vehicles may display abnormal Safety Connect operation during PDS due to DCM activation issues. This condition is characterized by no DTCs present and after the initial SOS light flashing sequence after ignition on, neither the red nor green light stays on in the overhead console. To determine if a vehicle is experiencing this condition, connect a Techstream and navigate to: Telematics-Data List - ?Telematics Activation Status?. If this value is displayed as ?Shipping?, continue to the recommendations below, and do not create a TAS case.
T-TT-0593-20_Rev2020-02-18. Service bulletin. ELECTRICAL SYSTEM. TT: Some customers may experience the inability to activate Remote Connect or Remote Connect becoming inoperative when attempting to send commands to the vehicle. To simplify the diagnosis of this system and prevent the unnecessary replacement of parts, please refer to the procedure below.
T-TT-0589-192020-01-27. Service bulletin. ELECTRICAL SYSTEM; EQUIPMENT ADAPTIVE/MOBILITY. TT: Customers may complain of a whine noise upon starter engagement. ? The whine noise may be accentuated when holding the key to start the engine; Alternately, the noise may be diminished by using the crank hold function ?bumping? the key to start the engine. ? The whine noise is likely to be loudest at the first cold start, diminishing with subsequent starts.
T-TT-0588-192020-01-27. Service bulletin. EQUIPMENT:OTHER:OWNERS/SERVICE/OTHER MANUAL; ELECTRICAL SYSTEM. TT: Some 2020 model year vehicles may display abnormal Safety Connect operation during PDS due to DCM activation issues. This condition is characterized by no DTCs present and after the initial SOS light flashing sequence after ignition on, neither the red nor green light stays on in the overhead console. To determine if a vehicle is experiencing this condition, connect a Techstream and navigate to: Telematics-Data List - ?Telematics Activation Status?. If this value is displayed as ?Shipping?, continue to the recommendations below, and do not create a TAS case.
T-SB-0161-192019-12-16. Service bulletin. ELECTRICAL SYSTEM; EQUIPMENT. TSB: Some 2020 model year vehicles equipped with Audio Plus (version 1021) or Premium Audio (version 1021) or earlier may exhibit one or more of the following conditions: ? Barge in function defaulted to ?OFF? ? Limited phone book grammar ? Difficult Hand Free operation ? Abnormal Electronic Owner?s Manual operation ? Music doesn?t automatically resume when using Android Auto ? Cover art isn?t displayed ?Vehicle position isn?t sent to Destination Assist server ? System inoperative after using the return button when using voice recognition A software update is now available to address these conditions. Follow the Software Update Procedure in this bulletin to update the software.
T-TT-0442-17_Rev2019-12-16. Service bulletin. ELECTRICAL SYSTEM; EQUIPMENT:OTHER:OWNERS/SERVICE/OTHER MANUAL; EQUIPMENT:ELECTRICAL:NAVIGATIONAL SYSTEM(GLOBAL POSITIONING SYSTEM). TT: Safety Connect is a vehicle option which requires a subscription fee for the system to be active after the initial trial period. Once the subscription has expired the DCM (Telematics Transceiver) will be in an inactive state. In some instances, a DCM may need to be replaced even though the customer is not using the service. If registration of the replacement DCM part is attempted using the Techstream utility after the account has become inactive, the registration will fail, and messages such as ?ATX webserver is Down? or ?ATX error? will be displayed.
T-TT-0571-192019-10-15. Service bulletin. ELECTRICAL SYSTEM. TT: Some 2020 model year Tundra and Sequoia vehicles may experience a B15DB or intermittent Wi-Fi inoperative (Wi-Fi icon greyed out). To simplify the diagnosis of the inoperative Wi-Fi, refer to the procedure below to prevent unnecessary parts replacement.
T-TT-0553-192019-09-03. Service bulletin. ELECTRICAL SYSTEM; EQUIPMENT. TT: The new DCA-8000 Diagnostic Charger may cause your facility?s Ground Fault Circuit Interrupter (GFCI) breaker to trip. A GFCI breaker can be tripped for various reasons, one of the reasons may be related to the DCA-8000. We are investigating this issue to determine the root cause. Other reasons the GFCI breaker may trip ? Circuit demand is too high for GFCI rating ? Worn out GFCI internal contacts ? Improper installation or wiring of GFCI breaker
T-SB-0134-16-Rev2019-09-03. Service bulletin. POWER TRAIN; ELECTRICAL SYSTEM; ENGINE. TSB: REVISION NOTICE July 01, 2019 Rev2: ? Applicability has been updated to 2019 ? 2020 model year Toyota vehicles. ? The Techstream Preparation and Process Overview sections have been updated. October 30, 2017 Rev1: ? Applicability has been updated to include 2018 model year vehicles. Any previous printed versions of this bulletin should be discarded. SUPERSESSION NOTICE The information contained in this bulletin supersedes SB No. T-SB-0012-13. Service Bulletin No. T-SB-0012-13 is obsolete and any printed versions should be discarded. Be sure to review the entire content of this bulletin before proceeding. 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 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. NOTE ECU is a Toyota term used to describe integrated computerized devices responsible for managing the operation of a system or subsystem. For the purposes of this bulletin, the term ?ECU? is used as a generic label for the following SAE J1930 standard references: ? Powertrain Control Module (PCM) ? Engine Control Module (ECM) ? Transmission Control Module (TCM) ? Any other Toyota specific control unit
T-TT-0549-192019-07-15. Service bulletin. ELECTRICAL SYSTEM. TT: The new 12V Battery Warranty Testers (DSS-5000 & DCA-8000) require certain information to generate a test result and warranty code. Below is an explanation of what information is required when testing a 12V battery on the new Warranty Battery Testers.
T-SB-0007-192019-02-19. Service bulletin. ELECTRICAL SYSTEM. TSB: A battery in a stored vehicle is subject to conditions that can reduce its performance and life. These conditions include storage period, temperature, parasitic drain, and battery load. Because of these factors, battery inspection and maintenance are required in order to ensure proper operation and optimal battery life. As a matter of policy, Toyota does not provide battery warranty coverage for discharged and/or failed batteries due to lack of maintenance. It is the dealer?s responsibility to maintain the specified State-Of-Charge (SOC) of the vehicle?s battery while in stock and ensure proper SOC at delivery. To eliminate customer service concerns due to an undercharged battery during the first few weeks of ownership, ALL dealers should check battery SOC and recharge, if necessary, within 48 hours of delivery to customers.

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