2019 Mazda CX-9

The engine cylinder head developed an internal coolant leak, allowing coolant to enter the combustion chamber. This caused engine overheating and smoke coming from the tailpipe while driving. A dealer performed a coolant pressure test confirming coolant leaking into the combustion chamber, and wet/dry compression testing on all 4 cylinders showed low and inconsistent readings consistent with cylinder head coolant intrusion (Cylinder 1: 105/125 psi, Cylinder 2: 115/125 psi, Cylinder 3: 110/175 psi, Cylinder 4: 160/190 psi). Overheating creates a risk of sudden loss of power and potential engine failure while driving, including on the highway. The problem has been confirmed and diagnosed by an authorized dealer service center, and the manufacturer's technical hotline department reviewed the diagnostic findings directly. Warning symptoms (overheating codes and visible tailpipe smoke) first appeared at the time the vehicle was brought in for diagnosis. The manufacturer has an active technical service bulletin addressing cylinder head coolant leaks on this engine and model, along with a related warranty extension program, but has denied coverage for this repair on the basis that the leak is internal rather than external.

NHTSA ID

11749615

Incident

May 30, 2026

My 2019 Mazda CX-9 (VIN [XXX]) suffered catastrophic cylinder head failure on the SKYACTIV-G 2.5T engine at approximately 124,000 miles. The failure is consistent with Mazda TSB 01-013/21 (and successors 01-007/22, 01-010/24), in which Mazda acknowledged that cylinder heads on this engine can crack at the stud bolt hole and exhaust manifold flange due to manifold deformation and residual production stress. The first warning came in mid-May 2026, when the engine temperature warning illuminated during normal driving. An independent mechanic replaced the thermostat. The warning returned within a week, and the thermostat was replaced a second time with a higher-quality part. Four to five days later, the warning returned alongside more severe symptoms: the vehicle began jerking while in motion, a strong coolant-burning smell developed, and smoke was visible from the exhaust pipe upon shutdown. The vehicle became undriveable, had to be left at the failure location, and was towed. Safety risk: The jerking compromised vehicle control in traffic. Upon shutdown, smoke and burning coolant odor created fire and fume-exposure risks. Had this failure occurred at highway speeds or in heavy traffic, the sudden loss of engine power and erratic behavior could have caused a serious collision. Family members were in the vehicle during several escalating events. Confirmation: The vehicle was towed to an authorized Mazda dealership, where Mazda-certified technicians confirmed in writing that it is exhibiting the exact defect described in TSB 01-013/21 and that complete engine replacement is required. The diagnosis is formally documented and has been communicated to Mazda's warranty team. Mazda Customer Experience has been engaged since mid-May 2026 and acknowledged the issue. The vehicle is currently at the dealership and available for inspection upon request. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

NHTSA ID

11745033

Incident

May 18, 2026

- Coolant leak at cylinder head and turbo at only 63,000 miles. - Safety issue because no warning lamps or messages appeared and potential for car to overheat without coolant circulating in the system. Car could breakdown at worst time and location. Leaking coolant onto exhaust created potential for fire. - Problem has not been confirmed by dealer yet. Appointment is upcoming. - Symptoms of the problem were leaking coolant on ground, low coolant level, heater not working properly. - First appeared 1/29/2026.

NHTSA ID

11714720

Incident

Jan 29, 2026

Mazda has a current service alert ("SA", SA-001/23) for issues with their Gen 6 Infotainment Center Display, which covers issues (e.g. ghost touch, surface peeling, spider cracks, and white dots) and defects the occur on the primary display of the car. This display provides the driver with essential car operational information. This service alert applies to may of their vehicles in the 2014-2021 range, dependent on model. This VIN provided [XXX] ) is associated with a 2019 CX-9 that within the last month started displaying spider cracks at 2 of the 4 corners of the display. Even though this is a known (manufacturer) issue with other cars that utilize this display, the local Mazda dealership will not cover the replacement for this vehicle as the VIN range has not been included in this SA. The SA does not include CX-9s, but does include Mazda3 (Japan built) with applicable model years 2017-2018 (produced from June 27, 2016 to October 31, 2018). --> This 2019 CX-9 vehicle is Japan built, with a manufacture date of "10/18" (October 2018). Many other people are having this same issue [XXX] ). Please encourage Mazda to expand their Service Alert range for this repair, which should be free (product cost and labor should be both provided at no cost to the consumer) to replace since it's a material issue with the product, not an operator error.... as documented in their SA-001/23. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

NHTSA ID

11710439

Incident

Jan 9, 2026

The contact owns a 2019 Mazda CX-9. The contact stated that a State Inspection was performed on the windshield for cracks. The contact stated that while driving in the rain, the front windshield wipers turned on independently with the switch in the off position. The contact was unable to turn off the windshield wipers. The contact pulled over to the side of the road and turned off the vehicle. When the vehicle was restarted, the front windshield wipers had turned off. The contact stated that the failure persisted and worsened. The contact stated that occasionally the windshield wipers failed to turn off. The vehicle was taken to the dealer; however, no cause for the failure was found. The vehicle was not repaired. The contact purchased and replaced a sensor. Upon investigation, the contact became aware that the on and off switch for the front windshield wipers related to the sensor located on the front windshield. The contact stated that the sensor controlled the on and off switch and failed to function as intended. The contact stated that the OEM windshield provided protection against the sensor malfunctioning; however, if the front windshield was replaced with a non-OEM windshield, the windshield wipers would fail to operate as designed. The manufacturer was not made aware of the failure. The failure mileage was 56,199.

NHTSA ID

11706077

Incident

Sep 15, 2025

Mileage

56,199 mi

1. What component or system failed or malfunctioned, and is it available for inspection upon request? ANSWER: Engine failure due to overheating. 2. safety & indicators: ANSWER: During evening rush hour traffic on a 3 lane highway my car went into a form of engine power saving mode while i had children in the vehicle; this was almost catastrophic form my family and the other vehicles around me. there was NO warning. there were no previous issues with my vehicle, this was unexpected. 3. technician review: this is a known issue with no warning: The technician inspected your vehicle and found a concerning issue with the engine overheating. They scanned the vehicle and found a trouble code P111A, indicating the engine coolant reached a temperature of 251.6 degrees Fahrenheit, forcing the engine into limp mode. Based on their experience, the technician believes the engine likely reached much higher temperatures, potentially causing internal damage to the engine block. After a thorough inspection, they found no external coolant leaks, but upon using a digital borescope, they discovered evidence of coolant entering and being burned off in Cylinder 3. Given the severity of the issue, the technician recommends replacing the entire engine to ensure the long-term reliability and extended life of your vehicle. Services completed: - Scanned vehicle and found trouble code P111A - Inspected engine and found no external coolant leaks - Used digital borescope to inspect cylinders and found coolant entering Cylinder 3 Recommendations: - Replace the entire engine

NHTSA ID

11690498

Incident

Sep 28, 2025

I am reporting a serious safety issue involving a defective suspension part (lower control arm) manufactured by Dorman and purchased from an online auto parts retailer. On October 7, 2024, I ordered a Dorman lower control arm for my vehicle and had it professionally installed on November 7, 2024 at Johnston and Magwood Wheels & Tires. On November 8, 2024, at approximately 5:40 p.m., while I was driving and made a hard brake, I suddenly lost steering control and my front left wheel collapsed. Fortunately, I was the only one in the car and managed to avoid an accident. My vehicle had to be towed to a nearby shop (Kal Tire) and was later sent back to the original shop for further inspection. On November 12, technicians confirmed that the newly installed lower control arm had failed, which caused serious damage to the suspension. I paid $1,774.10 in repairs in order to make the car safe to drive again. This is extremely dangerous — if I had been driving on a highway or with passengers, it could have resulted in a major accident or injuries. When I contacted the retailer about the warranty, they only offered to refund the part itself and refused to take responsibility for the damages caused by this defective product. I believe this part should be investigated for safety defects. When I searched online, I noticed Dorman has had similar recalls on control arms, which makes me even more concerned. I am reporting this incident to NHTSA in hopes that you will look into this part to protect public safety.

NHTSA ID

11681737

Incident

Nov 8, 2024

While driving on highway I get a message on my dashboard "High Engine Temperature/Engine Output may be limited" warning message. I pullover and see that the cooland is low. I wait for thee car to cool down and fill with coolant. After 5 minutes of driving, get the same message on dash. I had car towed to Martin Mazda in Delaware. Diagnosis is that I need a new EGR valve and new engine $13,000. How coincidental it has the same symptoms as described in TSB and manifests itself differently and not covered? I even had my vehicle towed to John Kennedy Mazda in Pennsylvania and diagnosis is coolant is leaking into my engine. Too much of a coincidence and I am not the only Mazda owner experiencing this. My car is part of the VIN for the Mazda Powertrain Warranty Extension Technical Service Bulletin 01-002/23 (Feb. 10, 2023). The Mazda Techs are trained to not diagnose as such not to be covered under the warranty due to the enormous economic strain it will put on Mazda corporation. Mazda gets around the class action suits by offering the Warranty Extension but not honoring it. Mazda needs to own up to their mistake and turn this Warranty Extenions TSB into an actual Recall. Will it take an actual stall of the Mazda affected vehicle on the highway causing deaths for some corrective action to be taken?

NHTSA ID

11670073

Incident

Jan 12, 2025

This SA supersedes the previously issued SA(s) listed below. The changes are noted in Red. SA-061/25 12/17/25 DESCRIPTION If you encounter any type of electrical concern (e.g, dead battery, engine no start, DTC(s) stored...), interview the customer before proceeding with normal MGSS diagnosis by asking if any aftermarket devices have been installed. Aftermarket devices may be the cause of the electrical concern. Below are a few examples of unusual electrical concerns caused by aftermarket devices. Examples: 1. Devices connected to the DLC-2 (battery discharge/DTC stored) 2. Devices plugged into the 12V outlet 3. GPS tracking device (engine no start/battery discharge) 4. Dash cam (DTC stored) 5. Non-certified USB cable (Apple Carplay™/ Android Auto™ will not connect) 6. Over-sized wheels/tires (incorrect GPS location) 7. DTC C0023:14 8. Decorative trim and/or cover on the START/STOP ENGINE button Example 1: Some electrical devices connected to the DLC-2 connector by insurance or mobile phone companies may cause: Battery discharge. The device may disrupt the CAN system battery saver mode. • IDS/MMDS will not communicate with the vehicle due to poor DLC-2 connection. The aftermarket device may cause DLC-2 female terminals to spread open.

This bulletin supersedes the previously issued bulletin(s) listed below. The changes are noted in Red. 01-008/23 06/05/23 Some vehicles may exhibit rattling noises from the engine compartment and oil leakage from the drive belt auto tensioner. This may be caused by insufficient sealing at the drive belt auto tensioner damper when the auto tensioner fully operates under both high ambient temperature and high load conditions. To eliminate this concern, the shape of the drive belt auto tensioner damper has been changed. REPAIR PROCEDURE If the tensioner is found to be "No Good" after completing the Drive Belt Auto Tensioner Inspection, replace it with a modified part according to the instructions on MGSS online:

DESCRIPTION Some vehicles may require the replacement of a damaged VIN plate or vehicle certification label. To obtain a replacement VIN plate (bulkhead-mounted and visible through the lower-left area of the windshield), contact DAG (Dealer Assistance Group) using VIN Plate Request Form available on One Mazda. To obtain a replacement vehicle certification label (located on the B􀀀pillar or front door), contact your assigned DSM (District Service Manager) to place the order. If DSM contact information is not available, refer to the Dealer & Field Contact Directory.

This Service Alert supersedes the previously issued SA listed below: The changes are noted in Red. SA-011/24 02/12/24, 06/06/24, 07/29/24 DESCRIPTION Mazda has developed factory recommended scheduled maintenance services that support all major vehicle systems. Mazda recommends dealers follow the scheduled maintenance tables as cited in the vehicle-specific workshop manual or owner's manual. Services performed outside of Mazda's factory scheduled maintenance are not recommended. These services are unnecessary and create unneeded expenses for your customers. SCHEDULED MAINTENANCE Refer to the applicable Workshop Manual or Owner's Manual for vehicle -specific manufacturer scheduled maintenance. Workshop Manual - Refer to section 00-00 SCHEDULED MAINTENANCE. Owner's Manual - Refer to section 8 Maintenance and Care. b. Note: Please refer to the information below outlining the services not included in Mazda's Factory Scheduled Maintenance: IMPORTANT: Recommending fluid flushes when not necessary can lead to customer confusion and dissatisfaction. Fluid flushing for preventive maintenance purposes is strongly discouraged, unless otherwise specified in a published procedure (Owner’s Manual, Workshop Manual, Technical Service Bulletin, etc.).

This Service Alert supersedes the previously issued M-Tip(s) listed below. The changes are noted in Red text. MT-002/19 09/30/19 and 12/19/19 DESCRIPTION If an engine assembly is replaced after a catastrophic internal mechanical failure, clean the intake manifold internally before installing a replacement engine assembly. If the intake manifold is not cleaned properly, the replacement engine may fail prematurely. Metallic debris from the old engine (with catastrophic internal mechanical failure) may rest inside the intake manifold. When the new engine assembly is installed, debris in the intake manifold will be ingested into the new engine and cause internal damage. Clean the intake manifold internally to remove any debris from old engine before installing the new replacement engine assembly. If the intake manifold cannot be properly cleaned internally, replace it.

This Service Alert supersedes the previously issued SA(s) and TSB(s) listed below: The changes are noted in Red. SA-035/24 05/31/24 DESCRIPTION There is a concern that some water pumps are being replaced that are not faulty, due to signs of a very small coolant leak from the bleed hole. This Service Alert is to inform you about the water pump sealing mechanism and the criteria if replacement is necessary or not. A mechanical seal (A) is used for the water pump. This mechanical seal can seal coolant (B) by sliding a mating ring (C) against a seal ring (D). When the sliding surface temperature of the mechanical seal is more than 248 °F (120 °C) while driving, a small amount of steam (E) is leaked and bleeds through the bleeding hole (F). After drying, the steam leaves a green coolant deposit near the water pump bleed hole (F). This is a normal condition and does not require water pump replacement. The water pump should only be replaced if there is an accumulation of crystallized coolant near the bleed hole. When you encounter a water pump with coolant seepage marks, decide to replace it or not based on the following criteria using sample photos. NOTE: During the initial period of use*, the sliding surfaces of the seals may not yet be fully settled, which can temporarily increase the amount of leakage. Continued use will allow the surfaces to settle, reducing the leakage. Replacing parts that are already settled with new ones will increase the leakage again until the new parts become conditioned. Therefore, replacement should be avoided in this initial period of use. *As a guideline, this applies to vehicles with less than 1,860 miles (3000 km) of mileage.