2023 Acura MDX

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.

My 2023 MDX Type S is currently at Mungenast St Louis Acura. Transfer Case and Transmission are both being replaced at roughly 56,000 miles. I made a turn and heard a loud noise. Because I was under acceleration my car was hard to control when it happened. Scared me and immediately let off the gas.

NHTSA ID

11754719

Incident

Jul 24, 2026

The contact owns a 2023 Acura MDX. The contact stated that while driving at various speeds over a bumpy road surface or a pothole, there was an abnormal metallic sound coming from underneath the passenger’s side of the vehicle. No warning light was illuminated. The vehicle was taken to the dealer, where a technician informed the contact that the sound was common after 50,000 miles. The contact was later informed that the cause of the failure was undetermined. The vehicle was not diagnosed or repaired. The manufacturer was notified of the failure, but the assigned case manager failed to help. The failure mileage was approximately 50,000.

NHTSA ID

11750299

Incident

Mar 14, 2026

Mileage

50,000 mi

2023 Acura MDX Sport looses AWD randomly and vehicle becomes only FWD. This has happened many times now and I have taken it to the dealership but they claim they can’t recreate it and would not do anything further unless I change rear end fluid.. I paid for the service but still have the problem. This is getting dangerous as it is unexpected and alters the expected performance of the vehicle in critical turning situations which has led to two close calls of a broad side accident when turning and loosing AWD. There appears to be many more reports of this exact issue, I’m officially adding my name to the list.

NHTSA ID

11738489

Incident

May 16, 2026

While driving my 2023 Acura MDX at approximately 40 mph in rainy conditions, the vehicle experienced a sudden catastrophic failure without any prior warning lights or dashboard messages. The vehicle abruptly decelerated and felt as though the drivetrain or wheels were binding / locking. The vehicle lost the ability to accelerate normally and became effectively inoperable in traffic. After stopping, the vehicle resisted rolling freely even when shifted into neutral and required towing to the dealership. The dealership has since informed me that the front transfer case / transfer box experienced a catastrophic internal failure. Root cause and failure sequence are still being diagnosed by the dealer. The sudden nature of the failure, lack of warning indicators, and apparent driveline lockup behavior created a significant safety hazard and increased risk of crash, particularly given the wet road conditions and speed at the time of the incident. There were several near misses with other cars putting me and my family at significant risk. The vehicle is currently at the dealership pending full diagnosis and repair.

NHTSA ID

11737958

Incident

May 8, 2026

What component or system failed or malfunctioned, and is it available for inspection upon request? Transfer case and yes, it is attached the vehicle. How was your safety or the safety of others put at risk? At this time there is a leak and the power is being redistributed which could lead to loss of power at any times. Has the problem been reproduced or confirmed by a dealer or independent service center? Yea both. Has the vehicle or component been inspected by the manufacturer, police, insurance representatives or others? Manufacturer. Were there any warning lamps, messages or other symptoms of the problem prior to the failure, and when did they first appear? No. During a routine transmission service this was noticed that there was a leak, they did not fill the fluid in the vehicle up to monitor fluid levels.

NHTSA ID

11730367

Incident

Feb 26, 2026

The contact owns a 2023 Acura MDX. The contact stated that while driving approximately 5 MPH, the vehicle unexpectedly accelerated. There was no warning light illuminated. The contact stated that the failure had occurred on several occasions. The vehicle was taken to the dealer. The vehicle was not diagnosed or repaired. The manufacturer was not made aware of the failure. The approximate failure mileage was 71,000.

NHTSA ID

11730005

Incident

Apr 8, 2026

Mileage

71,000 mi

A little over one year after purchase, I began receiving dashboard warnings related to the air suspension and braking systems. I scheduled service with the selling dealer (located over two hours from my home). By the time of my appointment, the rear of the vehicle was visibly unstable and bouncing during operation. Upon arrival at the dealership, while the technician was driving the vehicle into the service bay, the rear air suspension bag exploded. Once the vehicle was raised on the lift, the opposite rear suspension bag also exploded. I was informed by dealership personnel that had this occurred while I was driving – regardless of speed – it could likely have resulted in a crash. The stated cause of failure was severely corroded rear stroke sensors. Including that incident, I have had a total of 5 corroded stroke sensors replaced within an approximately one-year time frame. This appears to be a recurring and systemic defect rather than isolated component failure. The repeated corrosion of critical suspension components in a nearly new vehicle raises serious concerns about moisture intrusion, improper sealing, or design defect affecting safety-critical systems. This issue creates a significant risk of sudden suspension failure, loss of vehicle control, and potential crash. I am concerned that other owners may experience similar dangerous failures without warning.The vehicle has been serviced only at an authorized Acura dealership, and all repairs are documented. Exact dates of each repair: 4/10/25 – Both rear stroke sensors (mileage: 13,632), 9/24/25 – Left rear, 2/6/26 – Right front, 3/20/26 – Left rear, Current mileage: 25,160

NHTSA ID

11726266

Incident

Mar 29, 2025

Unable to stop the car. Luckily no accident. Brake pedal was very hard to press and car didn't stop. Brake pedal became normal again in few seconds (5- 7 sec). Inspected car. nothing was stuck under brake pedal.

NHTSA ID

11722412

Incident

Mar 6, 2026

Tech Line Summary Article - Customers are complaining of a clicking noise from front of vehicle while turning at low speeds. This is a temporary solution to address the issue.

"Service Bulletin - A pop noise can occur from the rear roof area when turning into driveways, bumps, or on an incline due to, in some cases, the panoramic roof frame mounting bolts are unable to maintain the necessary clamp force. This can allow shifting, which may lead to a pop noise."

Dealer Message - American Honda Motor Co., Inc. (AHM) is searching for certain 2023-2025 MDXs with a client complaint of a no auto re-start condition after going into an auto idle stop. The push button ignition may or may not restart the engine. To better understand the cause of this condition, AHM would like to inspect the vehicle prior to you attempting a repair of any kind.

Tech Line Summary - Customers are complaining of a clicking noise from front of vehicle while turning at low speeds. This is a temporary solution to address the issue.

Dealer Message - American Honda Motor Co., Inc. (AHM) is searching for certain 2023-2025 MDXs with a client complaint of a no auto re-start condition after going into an auto idle stop. The push button ignition may or may not restart the engine. To better understand the cause of this condition, AHM would like to inspect the vehicle prior to you attempting a repair of any kind.

Service Bulletin - Customers are experiencing screeching, squeaking, rubbing, or scraping from the rear wheel area due to rocks are getting caught between the rear brake disk and splash guard.