2025 Acura MDX

107 complaints on file, page 1 of 6.

1. Filed Sep 28, 2026Failure Sep 25, 2026San Diego, CAElectrical system, Engine

   The Auto Idle Stop has activated normally at traffic lights, but on two occasions the engine shut off and then failed to automatically restart when I released the brake. A yellow warning light with an exclamation mark also appeared on the dashboard. The most recent incident happened yesterday, 09/25/2026. There have also been several other times when the engine did restart, but it took noticeably more effort or longer than normal to restart from Auto Idle Stop.

   NHTSA complaint 11767472
2. Filed Sep 26, 2026Failure Apr 17, 2026Germantown, MDElectrical system, Engine, Power train

   My 2025 Acura MDX completely stalled in active roadway traffic and failed to restart. The failure occurred during a routine stop in traffic, tied to the Auto Idle-Stop / restart sequence: when releasing the brake pedal to accelerate, the engine did not restart, leaving the vehicle completely dead and stranded in the travel lane, creating a severe risk of a rear-end collision. I brought the vehicle to an authorized Acura dealership for repair. The dealership diagnosed the issue and replaced the starter motor under warranty. However, shortly after picking up the vehicle, the exact same failure occurred again in traffic. The vehicle was brought back in, and the 12V battery and charging system were tested and deemed functional, but the vehicle continues to stall and fail to restart. Replacing the starter and testing the battery has not resolved this recurring defect, which leaves the vehicle intermittently immobilized in active traffic lanes.

   NHTSA complaint 11767195
3. Filed Sep 20, 2026Failure Sep 19, 2026Keswick, VAEngine

   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 complaint 11765668
4. Filed Sep 16, 2026Failure Sep 16, 2026Cypress, TXElectrical system, Engine

   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 complaint 11764853
5. Filed Sep 16, 2026Failure Sep 16, 2026Mechanicsville, VAUnknown or other

   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 complaint 11764819
6. Filed Sep 15, 2026Failure Sep 14, 2026Plaistow, NHElectrical system

   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 complaint 11764541
7. Filed Sep 12, 2026Failure Sep 12, 2026Sugar Land, TXElectrical system

   Battery keeps dying. Faulty starter leaving car stranded.

   NHTSA complaint 11763842
8. Filed Sep 12, 2026Failure Sep 10, 2026Randolph, MAElectrical system

   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 complaint 11763829
9. Filed Sep 10, 2026Failure Sep 9, 2026Canton, OHElectrical system

   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 complaint 11763310
10. Filed Sep 10, 2026Failure Sep 9, 2026Vickburg, MSElectrical system, Service brakes

    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 complaint 11763280
11. Filed Sep 9, 2026Failure Mar 25, 2026Pittsburgh, PAElectrical system

    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 complaint 11762996
12. Filed Sep 8, 2026Failure Sep 8, 2026Long Beach, NYElectrical system, Fuel/propulsion system

    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 complaint 11762658
13. Filed Sep 4, 2026Failure Sep 3, 2026Marlton, NJEngine

    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 complaint 11762274
14. Filed Sep 3, 2026Failure Aug 31, 2026Chantilly, VAEngine

    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 complaint 11761810
15. Filed Sep 1, 2026Failure Mar 13, 2026Vicksburg, MSElectrical system, Engine

    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 complaint 11761234
16. Filed Aug 30, 2026Failure Aug 16, 2026Baton Rouge, LAElectrical system, Power train

    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 complaint 11760772
17. Filed Aug 29, 2026Failure Jun 1, 2026Gary, INUnknown or other

    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 complaint 11760682
18. Filed Aug 26, 2026Failure Aug 26, 2026Atlanta, GAEngine, Unknown or other

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

    NHTSA complaint 11759837
19. Filed Aug 25, 2026Failure Aug 20, 2026Garden Grove, CAUnknown or other

    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 complaint 11759382
20. Filed Aug 25, 2026Failure Aug 23, 2026Fayetteville, ARElectrical system, Engine, Power train

    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 complaint 11759336