Service bulletin T-SB-0037-25

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)
Type	Service bulletin
NHTSA id	11019359
Published by NHTSA	2025-06-06
Manufacturer's number	T-SB-0037-25
Manufacturer's date	2025-04-18
Campaign id or software version	T-SB-0037-25
NHTSA component	ELECTRICAL SYSTEM

NHTSA's summary

Some 2024 – 2025 model year Grand Highlander and Grand Highlander Hybrid vehicles may exhibit a condition where the Blind Spot Monitor (BSM) system is inoperative, there is a BSM malfunction message on the multi-information display (MID), or the driving assist information indicator is illuminated, along with one or more of the following Diagnostic Trouble Codes (DTCs) present: •C1AB413 – Outer Mirror Indicator (Module "B" Side) Circuit Open •C1AB513 – Outer Mirror Indicator (Module "A" Side) Circuit Open The BSM sensor software has been updated to reduce the possibility of these conditions.

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

Electrical system

Trouble codes named

C1AB4, C1AB5

Vehicles listed
TOYOTA GRAND HIGHLANDER	2024, 2025
TOYOTA GRAND HIGHLANDER HYBRID	2024, 2025 (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.

Recalls for the same vehicles and component
25V595000	2025-09-11. ELECTRICAL SYSTEM: INSTRUMENT CLUSTER/PANEL

A recall listed here may apply to some of the same vehicles. Only the manufacturer can say whether it applies to one vehicle.

Other bulletins for the same vehicles and component
T-SB-0058-23 Rev1	2025-07-10. Service campaign. The air conditioning dye injection tool kit has been developed to aid in identifying the location of air conditioning refrigerant leaks. The procedures outlined in this Service Bulletin aid in locating, inspecting, and repairing refrigerant leaks.
T-TT-0779-25	2025-06-06. Service bulletin. To assist with the early detection and early resolution of audio related concerns you may be asked to recover MMR data from the head unit. The following steps are instructions on how to retrieve the data from the system and are only to be used when requested by FTS and/or FPE.
T-SB-0037-25	2025-05-15. Service bulletin. Some 2024 – 2025 model year Grand Highlander and Grand Highlander Hybrid vehicles may exhibit a condition where the Blind Spot Monitor (BSM) system is inoperative, there is a BSM malfunction message on the multi-information display (MID), or the driving assist information indicator is illuminated, along with one or more of the following Diagnostic Trouble Codes (DTCs) present: •C1AB413 – Outer Mirror Indicator (Module "B" Side) Circuit Open •C1AB513 – Outer Mirror Indicator (Module "A" Side) Circuit Open The BSM sensor software has been updated to reduce the possibility of these conditions.
T-TT-0779-25	2025-05-15. Service bulletin. To assist with the early detection and early resolution of audio related concerns you may be asked to recover MMR data from the head unit. The following steps are instructions on how to retrieve the data from the system and are only to be used when requested by FTS and/or FPE.
T-SB-0013-24 Rev1	2025-04-08. Service bulletin. The Immobilizer and Smart Key Reset is a feature that allows the registration of new keys when all master keys are lost. Once the system is reset, all previously registered keys will be erased and can never be reused. Another feature, Add/Remove Key, is also available. Once a key is removed, it can never be reused.
T-SB-0013-24 Rev1	2025-03-11. Service bulletin. The Immobilizer and Smart Key Reset is a feature that allows the registration of new keys when all master keys are lost. Once the system is reset, all previously registered keys will be erased and can never be reused. Another feature, Add/Remove Key, is also available. Once a key is removed, it can never be reused.
T-SB-0120-20 Rev2	2025-02-12. Service bulletin. OBSOLETE NOTICE January 30, 2025: This bulletin is now obsolete. Please see T-SB-0015-25.
T-SB-0015-25	2025-02-12. Service bulletin. Some 2021 – 2025 model year Toyota vehicles may require the download and installation of vehicle specific software or configuration software when the Electronic Control Unit (ECU) is replaced. GTS+ software has been modified to indicate when configuration software is required. A new Configure column has been added to the GTS+ Health Check Results screen to show when configuration software is available for a specific ECU.
T-SB-0111-20 Rev2	2025-02-12. Service bulletin. OBSOLETE NOTICE January 23, 2025: This bulletin is now obsolete. Please see T-SB-0011-25.
T-SB-0011-25	2025-02-12. Service bulletin. When certain vehicle ECUs are replaced, the ECU Security Key must be written in order for that ECU to communicate on the vehicle network. The GTS+ Software Health Check Results screen has been enhanced to help identify if a replacement ECU requires an ECU Security Key.