Most common 2020 Mazda CX-9 problems
Share of the 19 complaints; one complaint can involve more than one system. "~" is the median mileage when the problem started.
Mazda CX-9 complaints by model year
Best CX-9 years: 2015, 2022, 2020. Years to avoid: 2012, 2011, 2018, 2008, 2010. Compare all years →
2020 Mazda CX-9 recalls (1)
Seats › Mid/rear assembly
Mazda North American Operations (Mazda) is recalling certain 2020-2021 CX-9 vehicles equipped with 60/40 split bench second-row seats. The left-side second-row seat may unexpectedly slide forward during a crash.
Remedy: Dealers will replace the internal parts of the affected second-row seats, free of charge. Owner notification letters were mailed November 4, 2021. Owners may contact Mazda customer service at 1-800-222-5500, Option 4.
What 2020 Mazda CX-9 owners say
Engine & cooling
The vehicle will hesitate/stall while driving down the road. The vehicle has done this multiple times and has actually shut off on 2 different occasions while at a stop. on 2 occasions now the vehicle has not wanted to start. I have taken vehicle to Mazda dealership and they can never duplicate it. When they check for any codes, the vehicle computer does not give accurate times when happened. This last date I took it to them 6/9/25, the computer said it happened 4000 miles ago. The time before, I took it in the morning it happened, 5 min after it happened and the computer said it happened 10 starts ago. The last time, 6/9/25 they said they suspect fuel pump going bad, but until the vehicle gives a "check engine" light or dies all together they are not 100% sure. The vehicle is unsafe if it dies in the middle of the freeway/road with no warning to myself or the other vehicles around me. …
Some vehicles may have coolant leaks at the cylinder head around the exhaust manifold. There may be cracks at the stud bolt hole or at the outside of the exhaust manifold - from Mazda's TSB. Excessive coolant leak leading to engine-overheating and going into 'limp mode' couldn't drive faster than around 30 mph. Mazda has repeatedly declined help with goodwill requests and any further assistance. ref. https: [redacted]
Electrical system
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. …
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.
Driver assistance
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. …
On 10/12/2021 we were driving on and urban street when the vehicle infront of us signaled and initiated a right hand turn. At that point were we traveling approximately 20 mph, and we were driving with active cruise disengaged. When we were around 150 feet behind the vehicle taking a right when our CX-9 falsely engaged the emergency braking. Our car with our whole family in it locked up the brakes and stopped in 80 feet short of the car taking a right. The vehicle behind us only managed to stop 10 feet short of hitting us in the rear. It is in the 4 people in our vehicles opinion that this operation was both terrifying and dangerous to use and those following.
2020 Mazda CX-9 engines & fuel economy
| Engine | Transmission | Drive | MPG city / hwy / combined |
|---|---|---|---|
| 2.5L 4-cyl turbo | 6-speed automatic | FWD | 22 / 28 / 24 |
| 2.5L 4-cyl turbo | 6-speed automatic | 4WD | 20 / 26 / 23 |
EPA ratings. Class: Small SUV.
Frequently asked questions
Is the 2020 Mazda CX-9 a good car?
Based on 19 owner complaints filed with NHTSA, the 2020 CX-9 rates better than average: 46% fewer complaints than a typical year of the CX-9 at the same age. It is one of the best CX-9 years by this measure. Complaint counts don't account for sales volume or individual maintenance, so have any used car inspected before buying.
What is the most common problem with the 2020 Mazda CX-9?
The engine & cooling — 5 complaints, 26% of all complaints for this model year. Next are the electrical system (4) and driver assistance (3).
How many recalls does the 2020 Mazda CX-9 have?
There is 1 recall for the 2020 Mazda CX-9, the most recent from September 27, 2021 (mid/rear assembly). Recall repairs are free at any authorized dealer — check whether yours has been done with the VIN recall check.
What are the best and worst years of the Mazda CX-9?
The best years by complaints, compared at the same age, are 2015, 2022 and 2020. Years to avoid or approach with caution: 2012, 2011, 2018, 2008 and 2010. See the full Mazda CX-9 years comparison.
At what mileage do 2020 Mazda CX-9 problems happen?
The median mileage reported in complaints is about 14,000 miles; 67% of problems with a recorded mileage started before 50,000 miles.
Source: U.S. National Highway Traffic Safety Administration (NHTSA) — owner complaints through October 20, 2026, recalls and defect investigations; fuel economy from the EPA. Complaints are unverified reports and are not proof of a defect. How we rate model years.