There are 4 owner-reported electrical system complaints for the 2020 Mazda CX-9in NHTSA's database. These are unverified consumer reports and may not reflect confirmed defects.
The information screen is getting 'spider cracks" spreading across the face and turning opaque making the information unreadable. Mazda is apparently aware of this defect and issued a TSB for earlier models. Dealers were unhelpful and quoted $1000 - $3000 to repair depending on the VIN.
Vehicle randomly displays "smart brake system malfunction," "forward smart city brake malfunction" and " front radar system malfunction." This has been going on for at least a year. I will be driving on a highway, trying to accelerate and these messages will pop up. I'm not able to accelerate when these messages pop up and I have to turn on my hazard lights and pull over to the side of the road. The only thing that clears these warnings are for me to completely shut down my car and restart it. Luckily I have been able to get over to the side of the road on the highway without an accident, but these warning lights pop up when it's sunny out and there is no reason for the car to act the way it does. I took my car to the dealer the first time it happened and paid several hundred dollars for them to tell me that they don't know why it happened. There are several forums posted online with people having the same issues. Online posts say to make sure the sensors are clean and that the malfunction can activate if it's too hot, rainy, snowing or foggy? In my experience, it has happened only when it has been sunny. When the system decides to malfunction, the car will not accelerate, and it could make it easier for the car to be hit by another car. It's like the car just shuts down.
We were on the freeway and all of a sudden it stopped accelerating and the engine light, sensor light, and sensor warning came on. We could not accelerate, that became disabled and we had to pull over. My husband said our fluid levels were normal and he checked them all in the shoulder of the freeway. We turned the vehicle off then on again and all lights went away and we continued on. This is a safety hazard because the car would not accelerate while we were going 60 mph on the freeway. I quickly took a picture of the dash as this was happening so I can take it to the dealer.
The 2020 Mazda completely shut off following an exit from an expressway, turn under a bridge and slow down for a red light. The Mazda electrically shut off and coasted to a braked stop in the center lane of a 3 lane road. The entire electrical system went dead, no exterior lights, signals, instrument panel or radio. There was no warning, everything electrical just shut off. In a moving traffic situation the car could not maneuver or restart without being placed in PARK. (There is a history of Mazda CX 9's having a similar problem which sent the driver to the local dealership.) The car was restarted by shifting into Park and pressing the start button, all functions appeared normal as the driver moved it to a parking lot to review the situation. The driver was unable to re-create the complete shut down and finished the trip. The driver took the Mazda to the dealer following the incident and was asked to leave the Mazda for observation. The driver was notified by the dealership that the problem was being elevated to the national team for diagnosis. 10 days later the local dealer called the driver and said that they; nor the Mazda engineers in California; could reproduce the system shutting off or find any error codes. They wanted to return the car to the driver with no need for a repair. The driver spoke to the National Mazda help line and the representative was aware of the situation. The representative reiterated that engineers had been unable to find the source for the incident in the computer logs so they could not provide a remedy. The representative offered the driver the choose of a purchase buy back and a discount on the purchase of a new car.
Complaints are unverified consumer reports submitted to NHTSA. A high complaint count may reflect vehicle popularity, not defect severity. Data sourced from NHTSA public records.
Data synced from NHTSA on Apr 26, 2026