Acura RDX 2021

I have a 2021 RDX. Was on the interstate moving at about 70 MPH coming back from Missouri. Raining. Lots of semis creating huge following misty, hard to see rain. Decided to accelerate to pass a couple. Car nearly stalled and acted like it had lost a cylinder's worth of power. Turned on hazards, slowed, pulled over and lifted the hood hearing all kinds of unusual noises. Shut the car off and restarted. All was well. Turned all lane-keeping, etc. off including cruise. Drove the last 100 miles or so without incident. Called dealer and was told likely didn't pull a code. Don't worry and keep driving. Said to make sure front of car was clean. Duh!! I keep my ride spotless (unless driving in the rain). Called CA's Acura line. Absolutely no help. 2 different females had no idea what limp mode was. Read quite a bit since then finding out it could be the result of many things including problems that could damage the motor and/or tranny. WOW!!! Had never heard of "limp mode" before. Nice that no info on this possible problem was anywhere in any user manual. Car has performed flawlessly ever since. So far, I guess the rain had interfered with the "radar" system and confused the computer. I'm thinking about buying a 40 year old car that doesn't have any of the modern computers etc. Later found info regarding TSB 20-053 which explains the problem and proposed solution. 06-26-2022 06:52 PM

I’d like to report an issue with this vehicle’s app companion, AcuraLink. AcuraLink is the official app offered by Acura, which delivers features that allow an owner to control and manage their vehicle remotely. I use the app for remote smart. On 1/17 at approximately 8am, I opened the app and sent a command to start the vehicle. The command failed, and I received a failure message to indicate this. I tried three more times, each time receiving a failure message, so I gave up and manually started the car. Approximately 45 minutes later, the car was back in our attached garage, with the ignition off, and our garage door shut. I suddenly heard the car start while in the garage. I went out, shut the car off, and went back inside. Over the course of 30 minutes or so, the car started two more times, in my attached garage with the door shut. This is an extremely dangerous scenario due to the potential of carbon monoxide and dioxide exposure. If this had happened in the middle of the night, I would not have heard the car running in the garage. This may have resulted in grave consequences for my family. It was as though the app continued to send commands to the car even after failure errors were received by the operator. I reported the issue immediately to Acura and have heard nothing back. I searched for similar stories on the social media site Reddit under the Acura group, and found multiple Acura owners reporting the same issue.

While driving on a freeway for about 15 minutes at 65 MPH, the MIL indicator started blinking. The vehicle began to rapidly shake, while the engine power decreased significantly. The engine dramatically went from 65 mph to 35 mph causing a safety hazard while driving on the freeway as we attempted to exit and pull over safely. The vehicle is a 2021 Acura RDX and is driven approximately 10,000 miles per year. All maintenance has been performed in accordance with the manufacturer's schedule. It has not been involved in any collisions or other user risk other than normal driving in accordance with the approved use of the vehicles. Upon trying to restart the vehicle, the vehicle continues to violently shake while in park. Notification lights indicating Brake Failure, AWD failure, Check Emissions System, etc. There were no other indicators that there was an issue with the vehicle prior to this instance on 4/20/2024. In fact, the vehicle was viewed by Cerritos Acura for its regularly schedule service on 4/10/2024 and no issues were identified by the dealer. As far as safety, we were traveling with two young children and the location of the freeway did not have a safe place to pull over. The sudden reduction in speed also put us in risk with surrounding vehicles. This appears to be related to TSB 20-053, however, no communication have been identified or communicated by the dealers to the the owner/operator of the vehicle.

I own a 2021 Acura RDX that was purchased new in February 2021. In the 11,500 miles I have driven it, there have been zero problems until yesterday. However, yesterday, when driving on an Interstate highway at 70 mph, in the rain, while passing a semi truck, my Acura RDX suddenly went into limp mode and the check engine light began flashing. After pulling over to the berm, and driving in the limp mode to the next exit, I turned the engine off. When I turned the engine back on it functioned normally and the check engine light went out. The engine has functioned normally for the approximately 100 miles I have driven since that time. Since there is no problem now, I have not taken the vehicle to the dealer to be checked since I felt that they would find nothing. When looking up this problem I found that mine is not an isolated case, and this same thing has happened to other Acura RDX owners. For that reason I am reporting the problem. I have also written to Acura to tell them of the problem. This was a very scary situation to have the engine suddenly, and without warning, go into limp mode while on a busy Interstate highway. Fortunately, in this case I was able to safely get to the berm of the road, but that might not always be possible. I have no idea when this might happen again, which is also scary. It is also very strange that by turning the engine off and then back on the problem disappeared. If requested, I would be happy to have Acura look at my vehicle if it would help to find the root cause of this problem. Thank you for your review of this problem.

Two low-speed sudden unintended acceleration events while parking a 2021 Acura RDX. Incident 1 (July 2026): While parking at low speed, the car unexpectedly surged forward. Flew up the curb and hit a restaurant window, causing massive undercarriage damage. Active braking did not help and seemed to make acceleration worse. It only stopped when it wanted to. Incident 2 (August 2026): Two weeks after getting the car back from repairs, under identical low-speed parking conditions, a second sudden acceleration event occurred. Slamming on the brakes did nothing. It stopped after scraping a car wash vacuum pole, destroying the entire passenger side. Prior to these, the car exhibited erratic safety software behavior, including multiple phantom braking incidents where it slammed on its brakes violently with no obstacles present. I bought the car Certified Pre-Owned two years ago. The dealership repaired a known "popping sound" from the panoramic sunroof frame three times. This required extensive cabin/pillar teardown work, which may have disturbed internal wiring harnesses or grounding points linked to the electronic throttle control system. In both events, it felt like an uncontrolled amusement park ride—the engine loudly revving and taking over with zero driver control. I initially assumed pedal confusion during the first crash, but since it happened again under identical circumstances, there is clearly a systemic electronic/software defect in the Throttle Actuator or Powertrain Control Module. The vehicle is at an insurance network body shop awaiting forensic evaluation of the throttle system, pedal sensors, and a Bosch EDR black box download.

On July 21st, 2024, the electronic parking brake on our 2021 Acura RDX seized and would not release. The vehicle had not sustained any damage and only had 63,270 miles on the odometer. The vehicle was in the garage but the brake seizure rendered the otherwise functioning vehicle unusable. The vehicle is available for inspection. There was nothing to indicate a problem prior to failure on the 21st. An Acura dealer replaced the gear unit motor that actuates the parking brake but the brake did not disengage as per the repair invoice attached. It was determined the parking brake switch circuit connection did not match specs and the parking brake switch was replaced. The parking brake worked at the time we retrieved the vehicle from the dealership but currently do not engage the brake as we are unsure if this will fail again. This issue put us and owners of like vehicles in danger due to the fact that a simple switch malfunction seizes the rear brakes of the car. Fortunately the vehicle was in our garage at the time but if failure occurs at speed, rear locked brake(s) could no doubt lead to a serious crash. At best, a parked disabled vehicle leads to very costly inconvenience as it did for us. Whether a failed switch or a poor connection my concern is the problem replicates while in motion while driving and losing control of the vehicle. From internet searches it appears failed switches are a growing problem with Honda vehicles equipped with electronic parking brakes. There exists no override ability to disengage the parking brake apart from the electronic switch. Again, an otherwise functioning vehicle can be disabled as the rear wheel(s) are seized.

The Auto High-Beam system activates the high beams inappropriately during operation. The system triggers the high beams directly into the eyes of oncoming traffic and activates during early dusk conditions. The sudden, intense illumination blinds oncoming drivers. This creates an immediate glare hazard and significantly increases the risk of a head-on collision. I reported this specific failure to the authorized dealership on three separate occasions, engaging three distinct service advisors during the active warranty period. The service department omitted these complaints from the formal repair orders. The first advisor stated the system was functioning normally. The second advisor stated the technicians completed an inspection and verified the system as fully operational. The third advisor acknowledged experiencing the exact same malfunction on their personal vehicle and instructed me to manually disable the safety feature. The system fails silently, displaying zero warning lamps or error messages prior to or during the malfunctions. The attached service invoices document a severe, underlying instability within the vehicle's electrical and Advanced Driver Assistance Systems (ADAS) network, culminating in a complete VSA modulator replacement. These records establish a confirmed administrative pattern of the dealership dismissing intermittent safety faults, officially logging statements such as "unable to verify issue" and "no problem found" on subsequent visits. This evidentiary paper trail substantiates the dealership's systemic suppression of my specific, repeated verbal reports regarding the Auto High-Beam safety hazard. The vehicle and the Auto High-Beam system remain available for inspection upon request.

On 12/22/22, I was driving in a 2021 RDX SH-AWD with my pregnant wife and 2 year old son from Media PA to Pittsburgh PA . It was rainy and 35-40 degrees F the whole drive. Approximately 4 hours into the drive we stopped at a rest stop on the PA turnpike to get gas. While attempting to merge back onto the turnpike from the service road to the right of the turnpike, a truck was coming up behind me in the right hand lane of the turnpike. I was traveling approximately 40mph on the service road, so I went to accelerate to safely complete the merge in front of the truck. Near the end of my acceleration sequence (I estimate I had gotten to approx 65mph) my car went into “limp mode”. I felt an unexpected and immediate loss of power and my check engine light/“MIL” began flashing yellow. I was luckily able to barely avoid a collision with the truck that was approaching. After the light started flashing I was unable to turn the knob to switch drive modes (it was in snow mode at the time this all happened). I was unable to do anything but attempt to drive to safety with severe power loss. I was able to coast my car with minimal accelerator response to the next exit off the turnpike and into a motel parking lot. I shut down the car and then turned it back on. When I turned it back on, the MIL light was no longer flashing and I had normal power restored to the vehicle, but interestingly the auto stop/start feature no longer worked. I was able to drive the remainder of the way to Pittsburgh without any further loss in power, though I was anxious the entire drive considering the major malfunction I had just experienced while attempting a merge at highway speeds. The vehicle only had approx 10,500 miles on it at the time of the incident. The vehicle is currently at the dealership being diagnosed. A case has also been opened directly with Acura/Honda.

Complaint about failure to execute recall and lack of solutions from the official dealer I, [XXX] , owner of a 2021 Acura RDX, VIN: [XXX] , am filing a complaint regarding the inadequate execution of a recall and the lack of solutions from the official dealer. What component or system failed or malfunctioned? The issue concerns the seat weight sensor, which is supposed to be replaced as part of the recall. How was your safety or the safety of others put at risk? Due to the malfunction of the mentioned component, the safety of passengers could be compromised, especially in the case of an emergency, where this component plays an important role in the safety system. Has the problem been reproduced or confirmed by a dealer or independent service center? The official dealer confirmed the need for the recall, but refuses to perform the replacement, citing the unavailability of necessary parts and offering no alternative solutions. Has the vehicle or component been inspected by the manufacturer, police, insurance representatives, or others? The vehicle was registered for the recall, but a specific inspection by the manufacturer has not taken place. Were there any warning lamps, messages, or other symptoms of the problem prior to the failure? At the time of contacting the dealer, there were no prior warning lamps or messages, but the situation requires immediate attention. Description of the incident and cause: Despite the recall being in place and the notification for the required repairs, the official dealer refuses to take the necessary action, citing the lack of parts, and does not offer any alternative solutions or specific timelines. This situation creates uncertainty and poses a potential safety risk. I kindly ask for prompt action to resolve this issue and ensure the recall is executed as soon as possible. Sincerely, [XXX] Contact information [XXX] [XXX] INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

What component or system failed or malfunctioned? Car automatically applied brakes on several occasions, despite no obstacles in front of the car. Incident 1: While driving through an 3-way intersection, the car slammed on the brakes automatically. There was a van in the opposite lane waiting to turn left. There was 2-3 feet of space so there was no risk of collision, but the car slammed on the brakes causing me to come to a sudden stop in the middle of the intersection. Incident 2: I was changing lanes to go past a stopped car in the left lane (It was waiting to make a left turn) The car automatically applied brakes, even though I would not have hit the car. Cars behind me had to slam on their brakes to avoid rear-ending my stopped car. Incident 3: While driving on a freeway at 65 mph with light traffic and no cars in front for at least 1000 ft the car flashed the automatic brake warning. It did not actually apply the brakes, but could have caused an accident considering the speed. Incident 4: While driving on a 2-lane road with cars parked on the sides of the road, the car displayed an automatic brake warning despite no collision being imminent. Incident 5: While driving down a suburban street with no trees or obstacles in sight, the automatic brake warning flashed. How was safety put at risk? Sudden stopping in a road, highway, or intersection could cause an accident. I am concerned for my safety, because if the car stops unexpectedly in the middle of the road, other cars may hit me. This is the same system used in some Hondas, so a recall of Honda vehicles may need to be extended to Acura vehicles. Has the problem been confirmed by dealer? Yes. The service advisor told me that his car has the same problem, but that it is normal and there is nothing they can do about it. Were there any warnings? Usually happens when there is a radar reflective object above or off to the side of the path of travel. The BRAKE warning appears when automatic braking is applied.

On or about XXX, my 2021 Acura RDX, with approximately 121,078 miles, suddenly displayed multiple dashboard warning lights and system-failure messages while I was driving. These included the check-engine light, Road Departure Mitigation System Problem, steering, stability-control, braking-assistance and other driver-assistance warnings. Earlier, the tire-pressure monitoring system had also indicated a malfunction even though the tire pressures were correct. The vehicle initially continued to drive and the conventional brakes appeared to function normally. However, it then began hesitating when I attempted to accelerate. The vehicle would eventually gain speed, but the initial hesitation created a serious safety concern when pulling into traffic or attempting to accelerate. The check-engine light remained solid while the vehicle was stopped but flashed whenever I began driving and accelerating again. No crash, fire or injury occurred. The vehicle had undergone a full diagnostic inspection approximately two weeks earlier, and I was informed that everything checked out properly. There were no known drivability problems before this incident, and the vehicle has been maintained according to the manufacturer’s recommended service schedule. The vehicle was subsequently inspected by Elite Acura, an authorized Acura dealership in [XXX]. The dealership confirmed a head-gasket failure and a problem with the rear differential left-side actuator. The dealer recommended replacing the head gasket, four spark plugs, coolant, oil and filter, as well as replacing the rear differential left-side actuator and changing the differential fluid. The estimated head-gasket repair was $5,391.46, and the estimated rear differential actuator and fluid service was $813.85. The dealer also recommended rear brake pads and rotors. The head-gasket and rear differential actuator problems were confirmed by the authorized Acura dealership. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT

Complaint Summary I am filing this complaint regarding American Honda Motor Corp’s handling of a warranty claim on my 2021 Acura RDX. Despite being within the 4-year/50,000-mile warranty, I was denied full coverage for a well-documented defect: condensation/moisture in both headlight housings with no external damage. •Dealer (Rick Case Acura, Sunrise FL) confirmed the condition. •Technician Francisco documented internal moisture, no external damage. •Service Manager Wade Bell submitted goodwill request [XXX], which was approved at 70% only. •My out-of-pocket responsibility was ~$1,400. •I requested full coverage from American Honda, consistent with Acura’s warranty obligations and known issues with these headlight assemblies. On a recorded call, American Honda repeatedly stated my request was denied, refused to provide a written denial, and declined to issue a case reference number directly. Only after reviewing an email did I locate the case number ([XXX]). This refusal to document their denial is highly concerning. ________________________________________ Timeline of Events •[XXX]: Moisture first observed after rain; confirmed by dealer technician. •Dealer Request: Goodwill [XXX] approved at 70%. •Repairs Completed: Both headlights replaced; repair order available. •Sep 2025: American Honda denied my appeal verbally on recorded call; refused written denial. ________________________________________ Manufacturer Guidance Ignored Importantly: American Honda’s own dealer service bulletin (2023) regarding 2019–2021 Acura RDX headlamps explicitly instructs dealers to: •“Create an iN case number (via AcuraLink/Dealer iN) when moisture or condensation is observed inside RDX headlamp housings with no external damage present.” •“Submit for goodwill/warranty replacement of the affected headlamp assemblies.” This vehicle falls squarely within that guidance: a 2021 RDX, <4 years old, <50k miles, with moisture documented by the dealer. Despite this, A INFORMATION REDACTED PURSU