2022 Acura TLX

On June 3, 2022, the Office of Defects Investigation (ODI) opened Preliminary Evaluation PE22005 after the agency received VOQs and several field reports concerning the Auto Idle Stop (AIS) feature on 2016-2019MY Honda Pilot vehicles. The complaints allege that the engine fails to restart on its own from a complete stop at a traffic light or road intersection with the AIS function engaged. The subject vehicles are equipped with a 3.5L engine with a 9-speed automatic transmission. On January 6, 2023, Honda released service bulletins 23-008 and 23-009. These service bulletins address the failure to restart issue in the 2016-2019MY Honda Pilot vehicles, as well as the 2015-2020 Acura TLX, 2016-2020 Acura MDX, 2019-2022 Honda Passport, and 2020-2023 Honda Ridgeline vehicles. The repair outlined in the service bulletins is a two-stage countermeasure to remedy the issue. The first stage is a Programmed Fuel Injection (“PGM-FI”) software update. The second stage is only deployed if the software update fails to remedy the issue. The second stage, depending on the model and model year, consists of replacement of the starter assembly, starter relays, and a valve adjustment. Additionally, Honda extended the warranty coverage to 10 years with unlimited mileage for vehicles requiring the second stage component replacement. ODI continues to receive complaints of the AIS failure to restart, with many complainants alleging the campaign countermeasures had been completed.NHTSA has reviewed Honda's Information Request Letter responses involving warranty claims, lawsuits, and consumer complaints in addition to ODI's own data. This Engineering Analysis is being opened to further consider the potential safety defect, including gathering additional data regarding Honda’s service campaign efficacy. ODI is additionally expanding the scope to encompass all vehicles addressed in Honda’s service bulletins 23-008 and 23-009 as well as newer model year vehicles, which are substantially similar to the vehicles covered by the service campaign. To review the ODI reports cited in the Opening Resume ODI Report Identification Number document, go to NHTSA.gov.

The Office of Defects Investigation (ODI) has completed its review of a Petition dated January 9, 2026, requesting an investigation into the loss of the optional all-wheel drive capability in model year (MY) 2021-2023 Acura TLX and MY 2022-2023 Acura MDX vehicles. The Petition alleges failures in the interfacing splines between the front wheel drive transaxle and the rear wheel drive power take off unit. Failure of these splines prevents the transfer of drive power to the rear axle, making the vehicle front wheel drive only. The Petition further alleges that this failure reduces vehicle directional control. Most traditional AWD systems utilize mechanical and passive measures. These systems have the tendency to distribute torque along the path of least resistance, such as a wheel that has lost contact with the ground or is on a low friction surface such as ice. To compensate for this, many manufacturers use the brake system to redirect torque to the wheels with more traction.  However, in this style of AWD system, a failed drive shaft or similar disconnection prior to the brakes often results in drive power being lost to the disconnected component. The consequence of this loss is the inability to maintain speed with surrounding traffic which increases the risks of collisions and injuries to the vehicle occupants. The Subject Vehicles are built upon a platform that was designed primarily as Front Wheel Drive (FWD). The SH-AWD system functions more as a performance enhancement feature rather than a stability feature. Even if the SH-AWD is nonoperational, the vehicles retain full mobility via FWD. In addition, the Vehicle Stability Assist (VSA) remains functional, ensuring directional stability through traditional engine and brake-based traction control. Although the condition raised by the Petitioner may degrade the vehicle’s performance characteristics, there is insufficient information to indicate a potential unreasonable safety risk. ODI reviewed 62 Vehicle Owner Questionnaires (VOQs) and several EWR Field Reports alleging the loss of SH-AWD and its impact on the driving dynamics of the subject vehicles. During its analysis, ODI determined that the failure is localized to the mechanical interface between the FWD transaxle and the PTU. Specifically, the failure is the shearing or stripping of the interfacing splined shafts between the FWD transaxle and the PTU, resulting in a permanent loss of torque transfer to the rear of the vehicle. Upon reviewing the technical details of SH-AWD, ODI has found that this failure does not result in any loss of motive power or lead to a loss of vehicle control. Several complaints indicated that the operators were unaware of the mechanical fault until encountering a low friction surface or the condition was identified by a technician during routine maintenance. The SH-AWD system lacks any form of direct feedback for monitoring real time torque transfer to the rear wheels. Therefore, the system will continue to display information indicating power is being supplied to the rear wheels even when power is actually only supplied to the front wheels. ODI’s review did not identify sufficient evidence to indicate that the misinformation has presented a safety issue in the field. ODI did not identify any reports of loss of motive power or vehicle control that could be attributed to the loss of SH-AWD. ODI is not aware of any crashes involving the Subject Vehicles that resulted from the loss of SH-AWD. After thoroughly assessing the material submitted by the Petitioner, consumer complaint information in NHTSA’s databases, and other relevant information already in possession of the Agency, NHTSA has not found sufficient evidence to indicate that the loss of AWD as alleged by the Petitioner is likely to present a safety related defect that would warrant a formal investigation. After full consideration of the available information, and in view of NHTSA’s enforcement priorities, the Petition is denied.  A denial report will be posted in the Federal Register.  The closing of the petition does not constitute a finding by NHTSA that a safety related defect does not exist, and the agency reserves the right to take additional action if warranted by future circumstances.  The Petition can be viewed at NHTSA.gov under ODI Number 11712885.

Transfer case failure, leakage, discovered after warranty expired. Took vehicle in describing seeming loss of AWD and tech informed me it was “normal” I Later discovered, during an oil change, a leak From the transmission or transfer case that covered the lower skid plate, which looking up, was directly related to a known failure of the Type S’s transfer case/Transmission causing a loss of traction to the rear wheels.

NHTSA ID

11750976

Incident

Apr 6, 2026

The transfer case splines sheared off in the transmission. The car is safe to drive but went from AWD to FWD as there is now no power being transmitted through the transfer case to the rear wheels. The dealership confirmed the issue was the transfer case by lifting the car and seeing if the rear wheels were getting power. They then tore down the transmission and found the splines were all gone from the transfer case. The component was not inspected by the manufacturer, police, insurance, or anyone else. There were no warnings or symptoms to the problem before the failure.

NHTSA ID

11750498

Incident

Jul 14, 2026

We have a 2022 Acura TLX Type S and it has started to show an errors - Adaptive Damper System Problem. From what I can gather from reviewing articles on the Internet is that this problem is caused because of poor wiring design by Honda / Acura, which is causing speed sensors electronics to erode. There are also articles that Honda /Acura is aware of this problem and is currently gathering data. Our concern is that in Michigan, if you have these problems, specially during winter when the roads are icy - if your drive type is stuck in the wrong mode - That can be a safety hazard. Example -The adaptive damper system can cause the automobile to be stuck in sports mode on an icy road, making it dangerous to drive............ Further, consumers are aware that this is a fault of the manufacturer, in the way the wiring harness is routed within the automobiles chassis. This poor design exposes the electronics to unwanted elements from road, snow, salt, dirt etc. It is also reported that this wiring harness is an expensive item to fix, hence Acura is reluctant in taking the necessary effort in resolving this very known issue. Consumers pay a lot for these vehicles for their quality - If this is a known issue , Acura should take care of it and not force the consumers to drive acuras with potential safety issues.

NHTSA ID

11749059

Incident

Jul 2, 2026

Went to the Acura dealer for an oil change. Was told I have a leak in the transmission and transfer case and that both will need to be replaced.

NHTSA ID

11746693

Incident

Jun 26, 2026

The transfer case spines have stripped and I no longer have all wheel drive only front wheel drive. This is a huge safety hazard for me .

NHTSA ID

11742990

Incident

May 20, 2026

Accelerated and heard a loud noise and felt like I had driven through wood and one got stocked to the whelle. There was a lot of traffic so I was driving slow. The noice I heard was like something was stuck inside the wheel, like it was grinding. Dealer diagnosed a bad transfer case and transmission and they replaced both under warranty.

NHTSA ID

11733872

Incident

Mar 9, 2026

Was changing the oil on my car and noticed grease running out from between the transfer case and transmission and also fluid build up on the transfer case higher up a little below the driveshaft. The car has 41k miles on it, there should be no leaks. My concern is the transfer case/transmission spline failure issue.

NHTSA ID

11733815

Incident

Apr 20, 2026

The contact owns a 2022 Acura TLX. The contact stated that there was an abnormal sound coming from the vehicle. The vehicle was taken to the local dealer, where it was diagnosed, and determined that the lower control arms needed to be replaced. There was no warning light illuminated. The contact was concerned that the control arms might fracture. The contact stated that the part to repair the vehicle was on back order. The vehicle was not repaired. The manufacturer was contacted and opened a case, but no additional assistance was provided. The failure mileage was approximately 72,845.

NHTSA ID

11729439

Incident

Mar 19, 2026

Mileage

72,845 mi

Over The Air Update - Vehicles equipped with the System Updates application are capable of downloading and installing Over the Air System Updates. System Updates contain upgrades that fix a variety of operational errors and/or enhancements that add new functionality. Information for the various software releases can be found in this document. Software version: D.1.6.4

Service Bulletin - Oil leak at the cam chain tensioner inspection cover due to and insufficient sealant adhesion on the inspection cover.

Dealer Message - American Honda Motor Co., Inc. (AHM) is searching for certain 2022- 2024 MDXs & 2021-2025 TLXs with a client complaint of a loose or detached rearview mirror bracket. To better understand the cause of this condition, AHM would like to collect specific parts from the vehicle prior to you attempting a repair of any kind.

Dealer Message - American Honda Motor Co., Inc. (AHM) is searching for certain 2021-2023 TLX ADV’s and 2021-2025 TLX Type S’s with a client complaint of the “Adaptive Damper System Problem” (ADS) error message on the MID (Multi Information Display). To better understand the cause of this condition, AHM would like to collect specific parts from the vehicle prior to you attempting a repair of any kind.

Dealer Message - American Honda Motor Co., Inc. (AHM) is searching for certain 2021-2023 TLX ADV’s and 2021-2025 TLX Type S’s with a client complaint of the “Adaptive Damper System Problem” (ADS) error message on the MID (Multi Information Display). To better understand the cause of this condition, AHM would like to collect specific parts from the vehicle prior to you attempting a repair of any kind.

Dealer Message - American Honda Motor Co., Inc. (AHM) is searching for certain 2021-2023 TLX ADV’s and 2021-2025 TLX Type S’s with a client complaint of the “Adaptive Damper System Problem” (ADS) error message on the MID (Multi Information Display). To better understand the cause of this condition, AHM would like to collect specific parts from the vehicle prior to you attempting a repair of any kind.