# Service bulletin T\-SB\-0021\-23

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.

- Type: Service bulletin
- NHTSA id: 10238131
- Published by NHTSA: 2023\-06\-26
- Manufacturer's number: T\-SB\-0021\-23
- Manufacturer's date: 2023\-05\-11
- NHTSA component: VISIBILITY:DEFROSTER/DEFOGGER/HVAC SYSTEM; ELECTRICAL SYSTEM

## NHTSA's summary

TSB: Some 2020 ? 2022 model year Highlander and RAV4 vehicles, and 2022 model year Tundra vehicles equipped with a start/stop switch may exhibit water entry to the vehicle from the HVAC drain hose being disconnected from the air conditioning radiator assembly and/or a grease/oil odor emitting from the vents. This condition may be caused by paraffin wax leaking from the evaporator.

## The document

- [NHTSA's copy of the document (PDF)](https://static.nhtsa.gov/odi/tsbs/2023/MC-10238131-0001.pdf)
- [If that address does not open, try this one](https://static.nhtsa.gov/odi/tsbs/2023/MC-10238131-9999.pdf)

The document is the manufacturer's. This site does not hold it.

## Components

Electrical system, Glass, wipers and mirrors, Heating and air conditioning

## Vehicles listed

- 2020 to 2022 TOYOTA HIGHLANDER
- 2020 to 2022 TOYOTA RAV4
- 2022 TOYOTA TUNDRA

## Recalls for the same vehicles and component

- [2025522](/recalls/tc/2025522.md), 2025-10-01: Visual System
- [2023382](/recalls/tc/2023382.md), 2023-07-12: Electrical
- [23V478000](/recalls/nhtsa/23V478000.md), 2023-07-12: ELECTRICAL SYSTEM:PROPULSION SYSTEM:DC/DC CONVERTER
- [2023084](/recalls/tc/2023084.md), 2023-02-22: Visual System
- [23V111000](/recalls/nhtsa/23V111000.md), 2023-02-22: ELECTRICAL SYSTEM: INSTRUMENT CLUSTER/PANEL
- [23V041000](/recalls/nhtsa/23V041000.md), 2023-02-02: ELECTRICAL SYSTEM:PROPULSION SYSTEM:HYBRID MANAGEMENT:POWER CONTROL UNIT/MODULE \(HPCU\)
- [2022374](/recalls/tc/2022374.md), 2022-07-13: Visual System
- [22V501000](/recalls/nhtsa/22V501000.md), 2022-07-13: BACK OVER PREVENTION:DISPLAY FUNCTION; ELECTRICAL SYSTEM:ADAS:PARKING ASSIST:SOFTWARE
- [2022215](/recalls/tc/2022215.md), 2022-04-28: Visual System
- [22V285000](/recalls/nhtsa/22V285000.md), 2022-04-28: BACK OVER PREVENTION:DISPLAY FUNCTION; ELECTRICAL SYSTEM:SOFTWARE

## Other bulletins for the same vehicles and component

- [26TC02](/bulletins/11034824.md), 2026-07-08, Service bulletin: ELECTRICAL SYSTEM. TECHNICAL INSTRUCTIONS FOR SPECIAL SERVICE CAMPAIGN 26TC02 REPROGRAMMING FOR PARKING ASSIST ECU CERTAIN 2022 \- 2024 TUNDRA / TUNDRA HYBRID
- [22TE09](/bulletins/11033412.md), 2026-06-04, Warranty extension: ELECTRICAL SYSTEM. Although the HV Floor Under Wire Harness and Rear Traction Motor Cable is covered by Toyota’s New Vehicle Limited Warranty for 3 years or 36,000 miles \(whichever comes first\), we at Toyota care about the customers’ ownership experience. Toyota is providing extended coverage under this Customer Support Program for repairs related to excessive corrosion to the wire harness connections at the Rear Motor Generator. Excessive corrosion can cause AM Radio Static during certain drive cycles, or the vehicle may not start.
- [26TC02](/bulletins/11031162.md), 2026-04-08, Service campaign: ELECTRICAL SYSTEM. SPECIAL SERVICE CAMPAIGN 26TC02 Certain 2023\-2024 Model Year Sequoia HV Certain 2022 – 2023 Model Year Tundra \& Tundra HV Trailer Back Up Guide Feature Inoperative Frequently Asked Questions
- [26TC02](/bulletins/11031160.md), 2026-04-08, Service bulletin: ELECTRICAL SYSTEM. TECHNICAL INSTRUCTIONS FOR SPECIAL SERVICE CAMPAIGN 26TC02 REPROGRAMMING FOR PARKING ASSIST ECU CERTAIN 2022 \- 2024 TUNDRA / TUNDRA HYBRID
- [26TC02](/bulletins/11031159.md), 2026-04-08, Service campaign: ELECTRICAL SYSTEM. After calibrating a trailer and using the Trailer Backup Guide feature, subsequent use of this feature may result in a “Trailer not detected” message or a blank multimedia display that prevents the display of features such as the backup camera. The multimedia system returns to normal if the vehicle is turned off and on again with no trailer attached.
- [T\-SB\-0021\-26](/bulletins/11031158.md), 2026-04-08, Service bulletin: ELECTRICAL SYSTEM. Some 2020 – 2024 model year Highlander and Highlander Hybrid vehicles may exhibit a condition in which the air conditioner does not cool due to a leak and/or corrosion in the rear underbody air conditioner tube and accessory assembly. The anti\-corrosion material has been updated to reduce the possibility of this condition.
- [T\-SB\-0106\-22 Rev2](/bulletins/11028726.md), 2026-02-11, Service bulletin: ELECTRICAL SYSTEM. OBSOLETE NOTICE January 30, 2026: This bulletin is now obsolete. Please see T\-SB\-0001\-26.
- [T\-SB\-0001\-26](/bulletins/11028722.md), 2026-02-11, Service bulletin: ELECTRICAL SYSTEM. Some 2018 – 2024 model year Toyota vehicles equipped with a Premium Audio with Dynamic Navigation System require a Special Service Tool \(SST\) USB flash drive to update the map, points of interest, and system software.
- [T\-TT\-0797\-26](/bulletins/11028713.md), 2026-02-11, Service bulletin: ELECTRICAL SYSTEM. Some RAV4 vehicles power seat where the automatic seat adjustment by the memory function does not work.
- [22TE09](/bulletins/11028711.md), 2026-02-11, Warranty extension: ELECTRICAL SYSTEM. Although the HV Floor Under Wire Harness and Rear Traction Motor Cable is covered by Toyota’s New Vehicle Limited Warranty for 3 years or 36,000 miles \(whichever comes first\), we at Toyota care about the customers’ ownership experience. Toyota is providing extended coverage under this Customer Support Program for repairs related to excessive corrosion to the wire harness connections at the Rear Motor Generator. Excessive corrosion can cause AM Radio Static during certain drive cycles, or the vehicle may not start.

JSON: [/v1/bulletins/10238131](/v1/bulletins/10238131)

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