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Service bulletin T-TT-0599-20 Rev

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.

The communication, as NHTSA indexes it (as of 2026-10-19)
TypeService bulletin
NHTSA id10190459
Published by NHTSA2021-04-19
Manufacturer's numberT-TT-0599-20 Rev
Manufacturer's date2020-03-16
NHTSA componentELECTRICAL SYSTEM; BACK OVER PREVENTION

NHTSA's summary

TT: Vehicle control apps might not operate as expected at times due to preconditions (normal operating parameters) not being established, vehicle settings and/or network/cellular coverage concerns.

The document

The document is the manufacturer's. This site does not hold it. NHTSA files a document at one of these two addresses; we have not asked NHTSA which.

Components

Driver assistance, Electrical system, Backup camera

Vehicles listed
TOYOTA 4RUNNER2020, 2021
TOYOTA AVALON2021
TOYOTA C-HR2020, 2021
TOYOTA CAMRY2020, 2021
TOYOTA COROLLA2021
TOYOTA COROLLA HATCHBACK2020, 2021 (the catalog's model; the bulletin names a series or trim of it)
TOYOTA HIGHLANDER2020, 2021
TOYOTA PRIUS2021
TOYOTA PRIUS PRIME2021 (the catalog's model; the bulletin names a series or trim of it)
TOYOTA RAV42020, 2021
TOYOTA RAV4 PRIME2021 (the catalog's model; the bulletin names a series or trim of it)
TOYOTA SEQUOIA2020, 2021
TOYOTA SIENNA HYBRID2021 (the catalog's model; the bulletin names a series or trim of it)
TOYOTA TACOMA2020, 2021
TOYOTA TUNDRA2020, 2021
TOYOTA VENZA HYBRID2021 (the catalog's model; the bulletin names a series or trim of it)

Listing a model year does not mean every vehicle of it is concerned: the document says which.

Other bulletins for the same vehicles and component
T-SB-0070-19 Rev2023-11-27. Service bulletin. TSB: Some 2015 ? 2023 model year TRD Pro Edition 4Runner vehicles may exhibit an abnormal noise when in Reverse with the wheels at or near full lock due to interference between the tire and bumper and/or fender liner. Follow the Repair Procedure in this bulletin to address this condition.
T-SB-0045-232023-08-28. Service bulletin. TSB: Some 2019 ? 2023 model year Tacoma Double Cab vehicles may exhibit a whine noise from the rear of the vehicle. This condition may occur while driving around 50 mph (80 kph) at constant speed, slight acceleration, or slight deceleration. This condition may be caused by rear differential vibration transferring through the chassis and body
20TE032023-08-28. Service bulletin. DP: This Customer Support Program provides coverage for a condition involving the front transfer case electro-magnetic clutch in certain 2019 ? 2020 model year RAV4 Adventure and Limited grade AWD vehicles. An abnormal buzz or groan noise from that case can occur with Normal drive mode selected during disconnect/connect timing of the AWD system. This condition typically occurs between 20 and 30 mph when accelerating from a stop, and/or between 20 and 13 mph on deceleration after driving the vehicle for 15 minutes or longer. Although the front transfer case electro-magnetic clutch is covered by Toyota?s New Vehicle Limited Warranty for 5 years or 60,000 miles (whichever comes first), we at Toyota care about the customers? ownership experience. Toyota is providing coverage for repairs related to abnormal buzz/groan noise from the front transfer case.
T-TT-0728-232023-08-28. Service bulletin. TT: This issue is currently under investigation. Please create TAS case and attach a store all health check. Please contact TAS for further instructions. If it is a weekend or a holiday, continue with diagnosis and repair. Please save all parts/ or details and contact TAS on the next available workday.
T-TT-0726-232023-08-28. Service bulletin. TT: Some 2021 - 2023 Highlander HV, RAV4 HV and Sienna HV vehicles equipped with Rear Motor Generator, MGR (Q610), may duplicate an abnormal noise (Drone, Growl, Humming, and/or other) from the MGR at various vehicle speeds and normal drive conditions. Please contact TAS for diagnostic instructions to aid in resolution of the condition.
T-TT-0732-232023-05-15. Service bulletin. TT: Confirm the vehicle meets the following conditions: 1) Rattle noise is coming from the brake pedal bracket assembly area AND not from other areas of the vehicle 2) Mileage is under 20,000 miles 3) Vehicle has not had previous front brake repairs performed 4) Vehicle is located in California or Oregon If the vehicle meets the above criteria, please create a TAS case. TAS will provide further instruction. If it is a weekend or holiday, continue with diagnosis and repair If the vehicle does not meet the above criteria, please proceed to diagnose the vehicle using the applicable repair manual.
T-TT-0726-232023-04-17. Service bulletin. TT: Some 2021 - 2023 Highlander HV, RAV4 HV and Sienna HV vehicles equipped with Rear Motor Generator, MGR (Q610), may duplicate an abnormal noise (Drone, Growl, Humming, and/or other) from the MGR at various vehicle speeds and normal drive conditions. Please contact TAS for diagnostic instructions to aid in resolution of the condition.
T-TT-0725-232023-04-17. Service bulletin. TT: Some 2021- 2023 Sienna HV vehicles may duplicate an abnormal noise (Growl, Humming and/or other) from the Hybrid T/A at various vehicle speeds and normal drive conditions. Please contact TAS for diagnostic instructions to aid in resolution of the condition.
T-TT-0724-232023-04-17. Service bulletin. TT: Some 19-21MY RAV4 Japan produced vehicles in Puerto Rico only exhibit a squeak type noise from the front suspension over bumps. Japan produced vehicles can be identified by VINs beginning with J.
T-SB-0014-232023-04-17. Service bulletin. TSB: Some 2019 ? 2021 model year RAV4 and RAV4 Hybrid and 2021 model year RAV4 Prime vehicles may exhibit a rattle noise from the sliding roof assembly when it is in the tilted open position while driving over a bumpy road. Follow the Repair Procedure in this bulletin to address this condition.