Owners have filed 19 complaints with NHTSA about this car, most about the electrical, engine, and fuel system. The 9 checks below target those problems, in the order you would do them at the car.
2020Tick items off on your phone at the car, or print it. Ticks stay on this device.
0/9 checked
2020 Mazda CX-9: inspection sheet
Before you go, or before you touch the car0/1
Engine off, key in hand0/1
Ask the seller not to warm the car up first0/5
At least 20 minutes, with some highway0/2
These checks are specific to this model year. For tires, body panels, fluids, and the other basics every used car needs, use the general inspection guide.
These years share the 2020's design and most of its parts, so their problems are the ones to look for on this car too.
Worth adding to your 2020 checks
Worth adding to your 2020 checks
Worth adding to your 2020 checks
EPA figures for each version of the 2020 Mazda CX-9. Use them to confirm you are looking at the version that was advertised, and as a yardstick on the test drive.
| Version | Drive | EPA rating |
|---|---|---|
| 2.5L 4-cyl | 4WD, FWD | 23–24 mpg |
NHTSA complaints for the 2020 Mazda CX-9, grouped by the part owners named. Open a row to read what goes wrong.
Warnings for the smart brake, smart city brake, and front radar systems appear without warning at highway speed, and the car then won't accelerate. Drivers have to pull over, and a full shutdown and restart clears the fault. Separate reports describe the whole electrical system going dead while moving, which leaves no lights, signals, gauges, or radio and lets the car coast to a stop in traffic. The information screen can also develop spreading spider cracks and turn opaque. Dealers quoted $1000 to $3000 for that repair.
Coolant leaks at the cylinder head near the exhaust manifold lead to overheating and limp mode, which holds the car to around 30 mph. Owners say Mazda turned down goodwill requests for this repair. Excessive oil consumption also shows up, with a quart needed in under 3000 miles. One report describes the engine revving on its own at a red light while the driver was braking. That is a loss-of-control risk, though the driver stopped safely by braking harder and shifting to neutral.
Rough running and sputtering get worse until the car won't go faster than 20 mph. In some cases it stops completely in the middle of the road, and every warning light comes on. The engine feels starved for fuel. Repair shops replaced a fuel injector and then a throttle body to address it. Other reports blame a faulty fuel pump that sets lean codes. Losing power in traffic is the main safety concern in this group.
A fuel cap warning light that keeps coming back can turn into jerking and vibration at stop signs. In one case the dealer traced this to a leaking charcoal canister at about 14,000 miles and said it was not covered by warranty. That repair cost $680. Overheating also appears here, with a reduced-power message repeating every few minutes and white smoke at startup. Topping off the coolant doesn't fix it, and mechanics suspect a coolant leak at the cylinder head.
Excerpts from complaints CX-9 owners filed with NHTSA, as written. Listen for the same symptoms on your test drive.
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.
Filed with NHTSA, February 2026
The mazda Cx-9 is having the same fuel pump issues that was recalled up until 2018 models. The issue with the lean codes and faulty fuel pump continues
Filed with NHTSA, June 2026
Complaints for this year next to the average for the other model years, area by area.
The 2020 ranks fourth for owner complaints among 6 CX-9 years, well under the average of the others. Newer years have had less time to collect complaints, so compare like with like.
Redesigns and mid-cycle updates change what can go wrong.
The 2020 is the fifth model year of the CX-9's second generation (2016–2024).
Recall repairs are free at any Mazda dealer, but the seller may never have had them done. Check each campaign number against the VIN.
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. As such, these vehicles fail to comply with the requirements of Federal Motor Vehicle Safety Standard number 210, "Seat Belt Assembly Anchorages.".
Risk: A seat that slides forward during a crash can transfer excessive force onto a belted occupant, increasing their risk of injury.
Fix: 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. Mazda's number for this recall is 5221I.
Cars shoppers compare with the Mazda CX-9, with their own 2020 checklists.
2020 owner complaints, side by side
