2024 Mazda CX-90 Plug-In Hybrid Engine Problems

Dear NHTSA Team, I am writing to formally report and follow up on a safety-related issue regarding my 2024 Mazda CX-90 PHEV, VIN: [XXX] . The vehicle has experienced repeated defects affecting critical safety systems, including: Engine overheating and cooling system failures Repeated engine malfunction warnings EVAP/emissions-related system faults These issues have persisted despite multiple visits to authorized Mazda service centers, and no permanent repair has been achieved. The defects raise serious concerns regarding the vehicle’s safety, reliability, and potential risk to road users. I have submitted a complaint via NHTSA’s Vehicle Complaint system but would like to confirm receipt and request the current status of my case, or any guidance on next steps. Please let me know if additional documentation, service records, or details are required. I am fully willing to cooperate to ensure this matter is properly reviewed. Thank you for your attention and assistance. Sincerely, Dr. [XXX] [XXX] Phone: [XXX] Email: [XXX] INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

NHTSA ID

11705472

Incident

May 14, 2025

I am reporting serious safety concerns with my Mazda CX-90 PHEV (leased, manufactured September 2023). These issues create unacceptable risk to occupants and other road users. Multiple Severe Recalls: My vehicle has had at least four major recalls: • 6323J – Engine & Motor Shutdown: Complete loss of propulsion without warning. • 7024J – ECU Software Failures: Loss of drive power and restart failures. • 24V817000 – EV Mode Power Loss: Sudden propulsion loss in EV mode. • 6724E – Sudden Braking: Automatic braking without cause. These defects could lead to crashes or fatalities. Hybrid System Malfunctions: Two recent “Hybrid System Malfunction” warnings required dealer visits. These failures could cause the car to shut off while driving—even at highway speeds. • First incident: Battery-related issue. • Second incident: Triggered by a loud noise during startup, impacting the AVAS system. A loud noise should never disable a family vehicle, indicating a design flaw. Charging Safety Issues: Charging via a standard outlet caused flickering lights and breaker buzzing in my house. A licensed electrician diagnosed harmonic distortion from the onboard charger. I spent $7,500 on electrical upgrades (dedicated EV line and panel upgrade) to charge safely. Manufacturer Response: I have had an open case with Mazda corporate for nearly two weeks. They refuse to acknowledge overall vehicle safety or provide written documentation confirming safety. Request: I urge NHTSA to investigate whether these defects represent a systemic safety issue in Mazda CX-90 PHEV models and take appropriate regulatory action

NHTSA ID

11704628

Incident

Nov 25, 2025

While driving 35 mph on a busy street, our vehicle completely lost power. The vehicle started violently shaking until I came to a complete stop. Many warning lights came on. Two primary: "Hybrid Malfunction", "Engine Malfunction" along with a couple others. When I stopped the car completely, it took 5 minutes before I could change the car from park to drive to move the car out of the way of oncoming traffic. Sitting in the middle of a busy road with hazards on is not safe!! Also, Suddenly losing power on a very busy street caused car behind me to slam brakes and honk at us. Very lucky we didnt cause an accident. If this had happened in a different situation such as freeway at 75 mph, major intersection, on a long roadtrip etc... the risk for significant disaster increase significantly! The car is current at Tum Dahle Dealership in Murray, Utah. This is the second time in 4 months we've had to take this car to the dealer for an issue. The first time was just an "Engine Malfunction" light. It sure seems like we bought a lemon. Even if they fix this car, my confidence is extremely low in this car being a safe car that im ok with having my family in.

NHTSA ID

11688799

Incident

Sep 19, 2025

Ever since the lease of this vehicle on January 2025 we’ve had problems with the brake/rotors took it in twice for that. As of recent August 2025, we took it in for loss of power going up a hill, hybrid malfunctioning electrical system going out. Dealership gave it back saying everything was fine. We took it on August 29, 2025 to Colorado vehicle failed to perform loss of power going up the mountain almost got hit by a vehicle because I was in a fast lane with my family had to pull over with whatever power I had left in the engine (not the battery). I mean the vehicle just keeps failing to perform as it should as well on the way back. It had the same issues but as severe going to Colorado.Vehicle does not change gears going uphill. When we stopped in Vegas for fuel, fuel door did not open it & malfunctioned. So vehicle does not perform well in cold and hot weather AWD system does not work at all. We feel a jerking, we hear a whistling’s type of noise that the dealership fell to inspect. Per them everything worked fine but when we took it to Colorado this weekend for Labor Day, vehicle underperformed with extreme safety concerns and we contacted Mazda, but they fell to listen to our concerns and say the vehicle is fine but when you drive the vehicle, it does not perform as it should and is a safety hazard to us and anybody around us due to a loss of power and everything I described above.

NHTSA ID

11684407

Incident

Aug 29, 2025

On two separate occasions, my young children were locked inside the vehicle, and on one of the two occasions my elderly mother was also locked inside. In all incidents, the doors and windows remained closed and would not unlock, even when attempting to use the key fob. Specifically, after parking, I exited the driver’s seat and closed my door. When I went to open the rear doors to get my children out of their car seats, the rear doors were locked and could not be unlocked by the key fob. The same occurred when my elderly mother was in the vehicle. Each time, the car was in hot conditions, and we were fortunately able — after some struggle — to unlock the doors and remove them from the vehicle. This presents a serious safety risk, particularly in warm weather and with young or elderly passengers who cannot exit the vehicle themselves. I am currently pursuing a lemon law claim for this vehicle, but I also wanted to formally report this defect because of the danger it poses.

NHTSA ID

11673421

Incident

Jul 12, 2025

Issue Summary: Since December 27, 2024, my vehicle has experienced a hybrid malfunction and leakage issue three times. Each time this occurs, the vehicle becomes completely inoperable and cannot move, requiring a tow truck to take it to the dealership. Since December 27, 2024, my car has been in the shop four times, yet the issue persists. This raises serious reliability and safety concerns, as the vehicle can suddenly become unusa

NHTSA ID

11644694

Incident

Dec 27, 2024

While vehicle was in motion, warning light came on stating “engine malfunction, have the vehicle inspected”. Engine light stays illuminated. The message and light now appear at startup

NHTSA ID

11641492

Incident

Feb 5, 2025

At approximately 16:50 engine malfunction warning light appeared and dealership was notified. Appointment scheduled for 4 days after. At 17:21 car began swerving uncontrollably along I80 with warning “engine malfunction, have the vehicle inspected.” The car was shaking violently and veered off the road into the ditch between the eastbound and westbound highway. The car was totaled. Review of the vehicle app indicated that just before the crash at 17:19 several critical vehicle malfunctions messages appeared. The vehicle crashed at 17:21.

NHTSA ID

11641436

Incident

Nov 21, 2024

This is a 2024 Mazda CX-90 PEHV where I took it in for all recalls on January 17th, 2025 related to loss of power and hybrid system malfunction. Today, Jan 31st, 2024 (2 weeks and a few 100 miles later), I now have engine malfunction warnings lights. This car has serious issues that nearly caused a bad accident where POST recall, the issues continue

NHTSA ID

11639858

Incident

Jan 31, 2025

1. Gear Shift Issue in EV Mode: The transition from 1st to 2nd gear is not shifting properly in EV mode. At times, the gear jerks during critical situations, which compromises control. 2. Power Output on Highway: While driving on the highway, there are instances where there is no power output when flooring the accelerator to overtake. 3. Engine Malfunction Light: The engine malfunction light has come on and off three times. 4. Radar Malfunction: The radar system is intermittently not working or working improperly. The radar malfunction light also came on and off once (i-ACTIVSENSE system malfunction). The last safety recall was completed a few weeks ago, but the issues are still ongoing. Since then, I have visited the Mazda dealership twice, but they let me go, dismissing my claims and saying they couldn’t duplicate the problems. I have a case with Mazda corporation. Nothing done yet (Case Number: [XXX]). The name of the Representative is Candy. I would appreciate it if you could investigate these issues at the earliest convenience. Thank you for your attention to these matters. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

NHTSA ID

11632007

Incident

Dec 6, 2024

I was driving my 2024 CX90 PHEV when a warning about an electrical leakage in the hybrid system was detected. I brought it home and parked in my garage. I called the dealership and they told me to bring it in. When I started to leave, the car would not shift out of park and bricked up. A towing service had to drag it out of my garage. My concern is that there is no limp mode or any way to switch to the gasoline engine when this happened. Had there been a fire in the battery, I would not have been able to get it out of my garage, putting our house and children at risk. Also, had it locked up on a highway, an accident could easily happen. After the dealership dragged it off of the rollback, they couldn’t even get the car to move. They told me that they would have to order special tools to be able to get the car to move. Along with the steering recall that worked for about a month, the steering rack had to be replaced, and the failure of the electrical system, I feel like this car is unsafe to drive. Thank you.

NHTSA ID

11623076

Incident

Oct 16, 2024

On my way to drop kid to school all of a sudden the car gave up power and shuddered with engine malfunction and I-drive malfunction warning. Check engine light came on. This is risky because another vehicle could have smashed into us if on highway or high speed. Research shows that a whole lot of people have this identical issue.

NHTSA ID

11620262

Incident

Oct 14, 2024

Warning Alert for Hybrid System Malfunction also I Activsense partially disabled notice on screen

NHTSA ID

11618993

Incident

Oct 9, 2024

Mazda CX 90 PHEV. When charging on 110 standard outlet or 240v dedicated breaker - Chargepoint charger, the car onboard charger/inverter backfeeds a loud buzzing / humming back through the electrical wire to the electrical panel. It also causes a buzzing/humming in other appliances and causes led lights in the house to flicker. This is with a 100amp breaker panel and a new upgraded 200amp breaker panel. May cause electrical issues up to electrical fire in other areas of the home. Scheduled diagnostic test in vehicle 10/1/24, but other owners report same issue on Mazda CX 90 online forums.

NHTSA ID

11615291

Incident

Sep 5, 2024

July 11, 2024 – Odometer – 7,604, Gas – Full, Electric – 19 Miles range - From work to Home, Receive the following errors “Engine Malfunction, Have Vehicle Inspected” and “Hybrid System Malfunction, Have Vehicle Inspected” warning lights come on. Cars behavior – Air conditioning motor running but not cooling air, Loss of power and car very sluggish (have to be careful at intersections), seems to maintain speed even when taking foot of gas and requires extra breaking, seems to be clunky when transmission upshifts/downshifts at times. When leaving work, did not seem to like being in EV mode even though fully charged (Chargers at work) and would switch itself out of that move and say unavailable. Outside air temperature 90 degree (Air Conditioning not working, very uncomfortable). This defect is dangerous and I serious concerns driving this car such as unpredictable loss of power when entering traffic and hesitation / unpredictability when hitting the accelerator. In addition, with the car maintain speed while not touching the gas pedal and requiring extra breaking is a scary. June 13 – Issue cleared and wanting lights were gone before I was able to take it in for service. July 25th – Recurrence of the same issue - Odometer – 8,162, Gas – Full, Electric – 14 Miles range - From work to Home, Receive the following errors “Engine Malfunction, Have Vehicle Inspected” and “Hybrid System Malfunction, Have Vehicle Inspected” warning lights come on. Cars behavior – Air conditioning motor running but not cooling air, Loss of power and car very sluggish (have to be careful at intersections), seems to maintain speed even when taking foot of gas and requires extra breaking, seems to be clunky when transmission upshifts/downshifts at times. When leaving work, did not seem to like being in EV mode even though fully charged (Chargers at work) and would switch itself out of that move and say unavailable. Outside air temperature 87 degree (Air Conditioning not workin

NHTSA ID

11604822

Incident

Jul 25, 2024

On July 15, 2024 this vehicle at 50 mph on cruise control suddenly flashed white warning words indicating problems with the cruise control and immediately thereafter started flashing “hybrid malfunction” and to return to service dealer. At the time of the hybrid malfunction warning which was right after the quick cruise control warning, the engine operation, specifically the gas pedal no longer delivered power to vehicle, either electric or gas. Additional warning was to pull off to the side and stop and turn off vehicle. This occurred and vehicle was pulled to the side put into park and turned off. Waited approximately 3 to 5 minutes and restarted the engine which started in gas with no electric although there was electrical charge on the battery. Was able to continue to our final destination approximately 15 minutes later and no more than 10 miles driven. Hybrid malfunction was still visible on the dash to include the warning stating that vehicle needed to go to the service department. Approximately an hour later, vehicle was turned on again with the same warning about the hybrid malfunction, however, engine started in electric. Drove vehicle to dealership and stated what happened. Dealership the next day stated that this was a phantom code known by Mazda, but no problems associated with the code. Vehicle picked up per service advisors request two days later. Mazda dealership stated that headquarters had eyes on this particular vehicle. A day later after the pick up Mazda dealership requested vehicle be brought back for a “DC box” repair. Dealership stated this process would take a week or thereabouts to replace this component. Vehicle currently in dealership service.

NHTSA ID

11603677

Incident

Jul 15, 2024

I was driving 65 mph and the hybrid system malfunction warning came up. Car dropped to 25mph - pressing the gas pedal would not increase the speed. Continued to coast with no acceleration until it came to a stop and shut off

NHTSA ID

11594863

Incident

May 10, 2024

4 weeks ago my wife was driving on a busy highway and lost propulsion. Hybrid System malfunction message. She was able to pull over before causing an accident and put the car in gas only mode. She never shut the car off and drove on to her destination. I met her and picked up the car and took it to the dealer. Car is new and has 5000 miles on it. Car has been at dealer for 4 weeks with no answers and several unanswered phone calls to customer service at Mazda Corporate. Been told that is is a software problem with no fix and no time frame of when there will be a fix. I do have a case number with Mazda. Today after threatening calls to invoke "Lemon Law" in my state Mazda has suddenly said that the car has a faulty inverter and that the part is available and will be replaced. My feeling is that they are just throwing parts at a problem. This car is unsafe and NHSTA should put pressure on Mazda to either resolve issue or buy back cars. The majority of the complaints listed here are the same. Please take action!!

NHTSA ID

11594049

Incident

May 18, 2024

On April 3rd, around 5:20 PM, while driving with my daughter on a suburban street, my Mazda hybrid experienced sudden brake failure as I approached a stop sign. Attempts to engage the brakes failed, but they unexpectedly resumed, allowing the car to stop safely. This incident triggered multiple dashboard warnings including "Engine Malfunction," "Hybrid System Malfunction," and "i-Activesense System Malfunction." The hybrid battery’s range indicator also fluctuated erratically between 1 and 4 miles. The primary malfunction involved the vehicle’s braking system, with concurrent issues in the engine and hybrid systems as indicated by the alerts. The vehicle and all related components, along with the computer fault codes, are available for inspection and further testing at the Mazda dealership. The brake failure significantly endangered the safety of both myself and my daughter, as we nearly entered an active intersection uncontrollably, which could have led to a severe collision, posing a grave risk to both occupants and pedestrians. Despite extensive diagnostics and approximately 33 miles of test driving under various conditions, the dealership was unable to replicate the brake failure, raising serious concerns about the braking system’s reliability and predictability. The dealership's technicians, in cooperation with Mazda corporate engineers, have inspected the vehicle and analyzed the diagnostic data and fault codes. As of April 19th, the car remains with the dealership for further analysis. No additional inspections by police, insurance, or independent service centers have been reported. The inability to reproduce the brake failure and the spontaneous nature of the dashboard warnings underscore the necessity for continuous investigation by Mazda. Without a clear resolution, my trust in the vehicle’s safety is deeply shaken, especially for driving in high-speed or heavily trafficked areas.

NHTSA ID

11584033

Incident

Apr 3, 2024

On [XXX], San Diego, CA. (car is new purchase of 1 month 1 week old, 1250 miles, outside temp of 60 degrees, 3/4 battery charge, full tank of gas) Slowed to a stop at a red light in morning rush hour traffic. Engine sputters and multiple warnings appear on dash, including "Hybrid System Malfunction" "I ActiveSense Malfunction" "check engine" etc etc. CAR DIES IN LANE OF TRAFFIC AND LOCKS IN PARK. Attempted to restart 5-6 times, car would start and die immediately with same warnings. 7th restart and engine starts but had to finish drive in sport due to "Hybrid System Malfunction". Per NHTSA and dealer, all previous recalls had been performed/addressed prior to purchase date of [XXX]. Left car with dealer on [XXX] to address and repair issue. Completely unsafe for vehicle to suddenly die in traffic, with no way to move to the side of the road. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

NHTSA ID

11576900

Incident

Mar 8, 2024

On [XXX], I was driving on [XXX] near Pasadena at normal speed of traffic when suddenly an error message “Hybrid System Malfunction” appeared on the dash board along with check engine light, and the car began to stall slowing down to nearly full stop almost immediately. When I pressed gas pedal, it would not accelerate. Because I was in the far right lane, I had just about enough time to pull over onto the shoulder before the car stopped completely. The car was in EV mode (using all electric power) when this incident occurred with 20 miles of electric range still left. I was lucky that no cars were right behind me as the traffic was moving about 60 mph or my car could have been rear-ended when it came to such an abrupt stop. I put the car in park and turned off the engine, then turned it back on after a couple of minutes. The dashboard was flashing “Hybrid System Malfunction” and “check engine” light was on but I was able to drive it because it had switched to gas power mode. I immediately drove the car to New Century Mazda in Alhambra where I purchased it on [XXX]. The Mazda app on my phone captured two Vehicle Issues Detected at the same time: Hybrid System Malfunction: There is a possibility of restricted power output” and “i-ACTIVSENSE malfunction.” The Hybrid System Malfunction was the most serious and frightening of a series of malfunctions that my car experienced since it was purchased two months ago. On [XXX] (4 days after purchase) the car displayed “Approaching Vehicle Audible System (AVIS) Malfunction,” on [XXX], a “Brake!”light came on when we started the car after it had been parked, which disabled the steering wheel and the gear shift preventing us from driving (problem resolved by turning the car on and off several times). On [XXX], another vehicle issue was detected: “Air bag system and seatbelt pre-tensioner system malfunction.” Car was fully inspected by Mazda dealer in mid-January. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

NHTSA ID

11573765

Incident

Feb 23, 2024

While driving CX90 PHEV vehicle, a "HAZARD" error displayed on the dashboard and the vehicle stopped driving/accelerating completely. Displayed error reported a Hybrid System Malfunction and instructed driver to switch from hybrid to normal setting. Vehicle would not accelerate despite switch to normal setting and power remaining. Driver powered off vehicle and error remained on display. Driver again powered off vehicle after short wait and error was no longer displayed. Vehicle could then be driven in normal setting. Dealership and manufacturer have been notified with a request for immediate assistance. Vehicle is new and has only been driven for approx. 6 months. No advance warning signs appeared. Internet search reflects a Mazda owners' forum page [XXX] suggests that error has been known for several months with no resolution or recall. A vehicle that shuts down while driving in traffic is a hazard to us all. Responses are requested from both Mazda and NHTSA. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

NHTSA ID

11569956

Incident

Feb 4, 2024

Vehicle is in normal mode with EV mode engaged, car is going 70mph and suddenly accelerator stops working and decelerates to ~60mph until vehicle suddenly aggressively switches to gas mode and accelerates again.

NHTSA ID

11568848

Incident

Jan 4, 2024

CX90 PHEV Premium Plus new purchase 12/2023. 1/24/2024: "Hybrid System Malfunction, Have the vehicle Inspected " On a busy freeway with big rigs and other cars during rush hour traffic (5:25pm), going about 70 MPH. Only 1700miles on car so far. 50-60 degrees Fahrenheit outside. 2mi left on charge, full tank of gas. Car completely unable to accelerate all of the sudden on busy highway once this light came on. Was able to pull off to shoulder, albeit challenging as unable to accelerate and navigate through fast cars in right 2 lanes. Was able to restart car, and go at limp speed but unable to get fast enough to merge back. Called tow truck. Car towed to Mazda dealership. Then unable to get off flatbed of the tow truck as would not go into reverse. Tow guy called me and the staff at Mazda called their Service Manager, had to reset that code. (Something glitch kicked in and locked the car from being able to shift gears). Mazda Service was responsive, worked on and got diagnostics the next day. Stated that it was a computer system glitch. So they restarted the whole system. light is gone and car drives during their testing. They can't explain it. So computer and electronic glitch and system misread leads to a MECHANICAL malfunction that stops the car to be able to be accelerated on freeway. I am a mom of 3 young kids, and lucky I am alive.

NHTSA ID

11568058

Incident

Jan 24, 2024

What component or system failed or malfunctioned, and is it available for inspection upon request? "Hybrid System Malfunction. Stop Vehicle in a Safe Location." Car completely inoperable. Had to tow to dealership as would not start or go out of park. Hybrid and High Voltage battery issues reported by multiple owners. This happened less than a month into owning the vehicle and with less than 1200 miles. How was your safety or the safety of others put at risk? Car deceleration on highway specific to this error reported by multiple owners. Has the problem been reproduced or confirmed by a dealer or independent service center? Uknown. Currently being serviced by dealer. Has the vehicle or component been inspected by the manufacturer, police, insurance representatives or others? Currently being inspected by the Mazda dealership I leased the vehicle through. Were there any warning lamps, messages or other symptoms of the problem prior to the failure, and when did they first appear? "Yes, just a week into having the vehicle (at 300 miles) a "Hybrid System Malfunction" error message appeared to "Have the Vehicle Inspected." Dealership had it in their Service shop for over 2.5 weeks and said nothing was wrong with it.

NHTSA ID

11567596

Incident

Jan 18, 2024