2025 Acura MDX Owner Complaints

Car engine went into idle mode while the Idle Stop was engaged while stopped on an expressway off ramp. Car engine did not turn back on and entire car shut down. It took about 1 minute to re-start the car and engine. Safety was compromised because car shut off in an unsafe location. No accidents or injuries occurred. This happened about a year ago and car battery and starter were replaced by the Acura Dealer November 2025. There were no warning lights or messages prior to this problem appearing. Prior to this event, car had been slow to turn over for about 1 week. I previously submitted a complaint to NHTSA in Fall 2025, case #11694662, when this happened the first time.

NHTSA ID

11765668

Incident

Sep 19, 2026

I own a 2025 Acura MDX A-Spec purchased in XXX from John Eagle Acura in [XXX]. The vehicle has less than 10,000 miles. Component/system: The Auto Idle Stop/start system has malfunctioned. During the past week, the engine unexpectedly shut off while stopped at red lights and stop signs approximately 4–5 times. When it was supposed to restart, the vehicle sometimes failed to restart normally and required multiple attempts. The vehicle and components are available for inspection upon request. Safety risk: These incidents occurred at intersections while I was stopped in traffic. When the engine failed to restart, I was unable to immediately proceed while vehicles were behind me, creating a potential collision and traffic hazard. I regularly have my two young children in the vehicle, making this especially concerning. Dealer inspection: I brought the vehicle to John Eagle Acura after experiencing the problem. The service advisor indicated that this is a known issue, and the vehicle was serviced for the concern. The failure occurred repeatedly in real-world driving, but I do not know whether the dealer was able to reproduce it during inspection. Manufacturer/other inspection: The vehicle was inspected by an authorized Acura dealership. It has not been inspected by police or insurance representatives. Warnings/symptoms: I received no prior notification or warning from Acura regarding this issue. The first incidents occurred during the week before my dealership visit. The engine shut off while stopped and then did not restart normally. I did not observe a warning lamp or message specifically indicating that the vehicle would fail to restart. After experiencing the problem, I learned that NHTSA has an ongoing investigation, EA25-004, involving Auto Idle Stop failures on Honda and Acura vehicles, including 2023–2025 Acura MDX models. I am submitting this complaint so these repeated incidents can be documented as part of NHTSA's review. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 5

NHTSA ID

11764853

Incident

Sep 16, 2026

The engine shut off at a red light via Auto-Stop and failed to restart, leaving the vehicle stranded in active rush hour traffic until a manual restart of the engine was performed. This issue has occurred multiple times now.

NHTSA ID

11764819

Incident

Sep 16, 2026

Auto Start/Stop At stop light car wouldn’t start after engaging Auto Start/Stop, had to turn on hazards, turn car off and restart with cars bearing down on me Monday 9/14, before entering traffic I stopped and Auto Start/Stop engaged but car wouldn’t start Got a jump and brought to dealership and they replaced starter motor

NHTSA ID

11764541

Incident

Sep 14, 2026

Battery keeps dying. Faulty starter leaving car stranded.

NHTSA ID

11763842

Incident

Sep 12, 2026

Auto start-stop system stalled my car at a red light few times. Also I can clearly tell starting/cranking it is lagging as well.

NHTSA ID

11763829

Incident

Sep 10, 2026

Car at a stop light, went into idle stop, and then shut off with an error message that to continue to drive, depress brake pedal and push switch. Car then needs to be restarted. This has happened 3 times in less than a week, so it is becoming concerning as a safety issue. The issue seems to be related to the starter and idle stop feature.

NHTSA ID

11763310

Incident

Sep 9, 2026

20 minutes after parking my car, it would not start. Several different codes came up on the gauges - BRAKE issue; hill issue;stabilization issue - multiple icons and warnings. I ended up having to be jumped off.

NHTSA ID

11763280

Incident

Sep 9, 2026

Occassionally when the "auto stop start" feature is on and I am stopped at traffic light, the engine does not restart when I release the brake and hit the gas pedal. I took my car into my local dealer and they replaced battery but I was also advised that I might not want to use the "auto stop start" feature because it is a real drain on battery. Even with the new battery, I have experienced failure of the car to restart after being stopped in traffic while the "auto stop start" is engaged. When in traffic and you expect the car to restart and it doesn't, it causes momentary panic and is very unsafe. I have been turning the "auto stop start" feature off every time I start the car to avoid this unsafe situation.

NHTSA ID

11762996

Incident

Mar 25, 2026

Auto Stop/Start fails to restart intermittently causing dangerous situations stuck at lights unable to move. Sometimes it restarts again after pressing the brake and ignition right away. Sometimes it takes a minute to restart. Either way it happens unexpectantly leading to being frozen until you figure out what is going on.

NHTSA ID

11762658

Incident

Sep 8, 2026

I was driving w a passenger on a busy 4 lane road and trying to make a left turn. When I tried to hit the gas after coming to a stop, my car would not move. I did not know what was happening, as it turned out the car had shifted into park and turned off. Extremely dangerous scenario. I had to take my foot off the brake, restart the the car and put it in drive again to move. I brought it to the dealer the following day, they said they fixed it with a gear shield as the trans had dirt in it and a new starter. However, yesterday, prob about 6 or so months later it happened again. I went directly to the dealer. They kept the car over night. Today I was told the my battery charge was too low and the auto idle engine on/off turned off due to it being not having enough charge. Totally different excuse than the first time. Also, when I dropped it off I was told someone else had dropped their 2025 MDX off that same day for the same reason. I am very concerned, worried and nervous when I drive it. It helps if I turn the auto on/off idle stop off, but I must do that every time I start the car as it resets each time the car is turned off. Obviously I forget sometimes. It is a major concern that I feel the dealership is not taking seriously or showing much concern for my safety. Thank you for your help.

NHTSA ID

11762274

Incident

Sep 3, 2026

I have a 2025 Acura MDX SH-AWD. Several times while stopped in traffic, the Auto Idle Stop system shut the engine off and the vehicle displayed ‘RESTART ENGINE.’ The vehicle did not restart automatically. I'm concerned that this could cause a safety hazard if it happens in traffic. I want to file a safety complaint.

NHTSA ID

11761810

Incident

Aug 31, 2026

When at a red light the engine cuts off and does not restart when foot comes off the brake. Sometimes it takes several minutes to start. We were stuck in an intersection and almost were rear ended. Took it ti the dealership. had a new battery up in. By the time we got home, it did it again. Took it back to the dealership, they replaced the started. No problems for 4 months. Now it is doing the same thing again, along with the air conditioner not cooling. The first time we took it in for oil change we told them it was not cooling and were told there was nothing wrong with it. Took it back this weekend and found out there is a compressor issue. The compressors are not available for repair. Other minor issues are codes are randomly appearing on the gauges and the screen blacks out.

NHTSA ID

11761234

Incident

Mar 13, 2026

The auto shutoff and restart system has failed multiple times causing the car to shutoff in the middle of traffic. This has happened in traffic on the interstate, on surface streets and in the drive thru line. Safety was put at risk as had to restart car in middle of traffic multiple times; once car would not restart at stop light. This could have caused an accident as vehicle was at a full stop with cars coming up from behind in the road. Dealer has replaced starter and relay twice. In less than 2 years, I'm on my third starter. Dealer has inspected vehicle multiple times. No warning messages or other symptoms before occurring. When the engine would not restart at intersection, warning message of "transmission system problem, apply parking brake when parked. See your dealer" Could not restart engine.

NHTSA ID

11760772

Incident

Aug 16, 2026

My 2025 Acura MDX has 21,000+ miles on it and the START STOP SYSTEM has stalled and failed to restart the engine at RED LIGHTS several times. This is a SERIOUS SAFETY CONCERN! Does Honda/Acura have a Technical Service Bulletin for this issue? Reading many other complaints on social media many people are looking for ways to electrically circumvent the Start Stop System but that voids the manufactuers warranty. I need help solving this problem through HONDA/ACURA the right way. Please help?

NHTSA ID

11760682

Incident

Jun 1, 2026

Idle Auto Start/Stop will not restart after cutting on leaving me stranded in traffic.

NHTSA ID

11759837

Incident

Aug 26, 2026

I am leasing a 2025 Acura MDX with approximately 16,000 miles, acquired new in June 2025. The A/C system has failed and only blows hot air. The vehicle is available for inspection. I first noticed reduced cooling Thursday evening, August 20, 2026. By Friday, August 21, when it was approximately 89°F, the A/C was no longer producing cold air. I restarted the vehicle twice and repeatedly turned the climate controls and A/C on and off, but only hot air came from the vents. No warning lights or messages appeared. I contacted Cerritos Acura on Friday and spoke with the Service Director. I explained the failure, but the earliest appointment offered was approximately a week and a half later. I asked if they could arrange service elsewhere or contact another Acura dealer for an earlier appointment, but both requests were declined. On Monday, August 24, I had to commute approximately two hours to work without A/C during heat advisory conditions. I became extremely overheated and was concerned I was approaching a heat-related medical emergency. I consider this a serious safety concern, especially for a nearly new vehicle. The problem has not yet been diagnosed because the dealer has not inspected the vehicle.

NHTSA ID

11759382

Incident

Aug 20, 2026

My 2025 Acura MDX suffers from a severe safety defect regarding the Auto Idle Stop (auto start-stop) system. When the vehicle comes to a complete stop at intersections or traffic lights, the engine shuts off as intended. However, upon releasing the brake pedal to accelerate, the engine completely fails to auto-restart.Instead of restarting, the vehicle drops out of the auto-restart sequence entirely, shifts itself out of drive, and displays a critical safety message on the dashboard: "To start engine: Brake + Push".This completely strands the vehicle in live traffic, forcing me to manually shift into Park, press the foot brake, and push the engine start button while traffic accumulates behind me. This creates an immediate rear-end collision hazard.The dealership has already attempted to diagnose and repair this issue under warranty by replacing both the vehicle's battery. This hardware replacement did not fix the problem; the failure continues to occur unpredictably less than a week (and 25 miles) after replacement. The root cause appears to be a software, Powertrain Control Module (PCM), or sensor tracking defect where the vehicle fails to recognize it is in an automated restart sequence.I am filing this complaint to be officially included in the ongoing NHTSA Engineering Analysis EA25004 regarding Honda/Acura Auto Idle Stop failures, as the current hardware recall remedies are entirely ineffective for the 2025 model year.

NHTSA ID

11759336

Incident

Aug 23, 2026

2025 Acura MDX – Auto Idle Stop Failure to Restart When my 2025 Acura MDX is stopped at a traffic light and the Auto Idle Stop system activates, the engine shuts off but on multiple occasions has failed to restart when traffic begins moving. The vehicle becomes immobilized in an active traffic lane. Vehicles behind me begin moving and honking while I am unable to move the vehicle. To regain operation, I have had to completely shut the vehicle off and restart it while stopped in traffic. I can prevent the occurrence by manually disabling Auto Idle Stop after starting the vehicle, but this requires me to remember to disable the system every time I drive. If I forget, I risk the vehicle shutting down and failing to restart at an intersection. This creates a serious safety concern for me and my passengers, including my child. I am concerned about being stranded in an intersection or other active traffic lane and potentially being struck by another vehicle. I believe the Auto Idle Stop system's failure to restart the engine presents an unreasonable safety risk and should be investigated.

NHTSA ID

11758463

Incident

Aug 16, 2026

The contact owns a 2025 Acura MDX. The contact stated that while at a stop, the vehicle lost automotive power, and all electrical features turned off. The vehicle was restarted and the battery warning light illuminated. The contact continued to drive the vehicle. The vehicle was taken to a local dealer where it was diagnosed, and the contact was informed that no cause for the failure was found. The contact stated that upon starting the vehicle, the vehicle was idling roughly. The vehicle was not repaired. The manufacturer was notified of the failure. The failure mileage was 17,400.

NHTSA ID

11758335

Incident

Aug 5, 2026

Mileage

17,400 mi

The vehicle intermittently fails to restart after the Auto Idle Stop system shuts the engine off at a traffic stop. When this occurs, the vehicle remains disabled until it is manually restarted. This has now happened repeatedly, including twice within one recent week. The vehicle was purchased new on November 27, 2024, and currently has approximately 27,500 miles. The repair history for this same issue is: •September 19, 2025 — 13,841 miles: Battery replaced. •January 27, 2026 — 18,481 miles: Battery replaced again. •February 4, 2026 — 18,814 miles: Starter replaced. •August 14, 2026 — approximately 27,500 miles: Vehicle returned again for the same continuing problem. Diagnostics were performed, but no repair or resolution was provided. Despite replacement of two batteries and the starter, the defect continues. Our most recent experience with the dealership was particularly concerning. We were essentially told that they could not identify the problem and could not provide any further solution. That is not an acceptable outcome for a vehicle that can shut itself off while stopped in traffic and then fail to restart.

NHTSA ID

11757405

Incident

Aug 5, 2026

The auto start stop shut down the car when stopping at a red light and had to fully restart the car. This has happend several times since I owned the car. Its a safety issue is you need to move the car in an emergency or potential to reended by traffice behind you that assumes you are moving at a light. In addition on restart of the car at times the car struggles to restart like the battery is weak or starter is bad. Again more of a safety issue and potential accident.

NHTSA ID

11757152

Incident

Aug 15, 2026

After an auto idle stop at a major intersection, car failed to restart automatically and was left stranded unable to restart the car. Car would not shut off or turn back on when using the power button and with foot on brake but had power but it was in limp mode - transmission warnings flashed and the D "for drive" on the screen at the drivers location. I called tripleA however before they showed up I was able to put the parking brake on and turn the car off and on ad it reset. This is similar to the issue was happening with my 2017 Honda Pilot where it would stall and not restart after the auto idle stop engaged. Very dangerous and difficult to troubleshoot when in that situation, surprised that this is still happening in Honda manufactured cars - this is very dangerous and needs to be addressed and investigated.

NHTSA ID

11757151

Incident

Aug 13, 2026

Hello! I am writing to report an urgent and serious safety failure involving my 2025 Acura MDX A-Spec and to request immediate investigation and action. The vehicle’s driver-assist systems - specifically the lane departure warning and forward collision warning - failed to operate. In addition, both the steering wheel and the accelerator became stuck, causing my vehicle to collide head‑on with oncoming traffic. These failures placed my life and the lives of others in immediate danger. I previously opened a case with Acura Contact and Client Relations (Case #16550271). To investigate my vehicle failures that caused this major accident, the response I received was inadequate and deeply concerning. During my conversation with Acura representatives, I was told verbally without any willingness to provide this statement in writing that Acura “has nothing to do with inspecting their own car.” Instead, I was instructed to have my vehicle inspected by my insurance company, despite the fact that they are not certified to evaluate Acura safety systems and do not possess the diagnostic equipment required to assess failures of this nature. Given the severity of the malfunction and the resulting collision, I am requesting that Acura immediately arrange a proper inspection by qualified Acura technicians and provide a written explanation of how such critical safety and control systems could fail simultaneously.

NHTSA ID

11757146

Incident

Aug 7, 2026

The automatic engine shutoff turned off the engine three times at stop lights and failed to restart. We were left stranded in the middle of the road, cars zipping by us fast. We felt very much at risk of being hit.

NHTSA ID

11757065

Incident

Aug 1, 2026