2020 Mazda CX-30 problems

Filed Oct 6, 2026 · Engine · MO

Multiple fixes and repairs on a P0421 code. Repaired by Mazda with a new catalytic converter but then refused to replace it when the code came back saying it was not covered by the warranty. Mazda says it is not a common issue but they have had issues in the past with the same P0421 code repeatedly showing up on a healthy car.

Filed Sep 3, 2026 · Transmission · MO

My car was squeaking and lurching around 3/4 gear. I took it in to the Mazda dealership (Northtowne Mazda in Kansas City) and they told me it was a "well-known issue" with this year and make of a Mazda. There is a problem with the torque converter lock-up clutch which sheds iron particles into the transmission fluid. The torque converter needs to be replaced. After further research, it appears that Mazda has a well-documented manufacturing defect that is outlined in Mazda TSB 05-005/23. My car has a 60,000 mile/5 year warranty on it. It currently only has 48,600 miles on it (well under the warranty limit). I called the Mazda Corporation Customer Care and they opened a ticket but I was told today that they will not extend any assistance with this, even though it is below the warranty limit on mileage and with them knowing about this issue and publishing a bulletin about it. I asked about the Good Will extension and the Customer Service Case Manager told me it didn't qualify. Even with it being under the warranty mileage, because it's over the year limit, they won't cover it. I asked what the criteria was to qualify for the Good Will extension and he told me it was "confidential" and there is nothing they can do about it.

Filed Jul 18, 2026 · Lights · PA

The front passenger side headlight is making a whirring noise whenever the light is turned on. Based on the federal safety agency safety reports for this model, this indicates the fan is failing, and soon the headlight will also fail. Intact headlights are essential for driving safety at night. No warning messages have appeared on the car.

Filed Jan 10, 2026 · Electrical · NY

My 2020 Mazda CX-30 has an intermittent no-start condition caused by a complete electrical failure. This occurs randomly, often overnight and after long or short trips. When it happens: The car does not respond to the key fob or ignition Dashboard warning lights are off Vehicle cannot be started, creating a safety risk if it occurs during travel or in an emergency The defect began during car's full warranty period and has persisted despite multiple service visits and battery replacement. The dealer has been unable to diagnose or correct the issue, and Mazda Corporate is aware of the defect under case Case Number 00398310. After about two years of these intermittement failures, and parasitic draws ruled out, I paid to have the Battery replaced, independently of Mazda and the battery failed yet again. Routine diagnostics have not resolved the defect Issue is intermittent and unpredictable This is a Safety Risk as the Car has failed to start when needed on numerous occasions, and has left me stranded. ALL of these Failures have occured without warning Mazda Corporate is aware and has requested dealership diagnostics. Dealership has not reproduced the problem. Issue remains unresolved as of 1/10/2026 Video documentation exists showing dealer inspection and inability to find failure source. I am submitting this complaint to the federal safety agency because the defect: Impairs the vehicle’s safe operation Has not been reliably repaired Represents a potential safety risk to the driver and public I request that this complaint be recorded for investigation and included in any potential recall or safety evaluation. Service records available on request Emails with Mazda Corporate als available Video of dealer inspection showing intermittent failure avaialble

Filed Nov 30, 2025 · Brakes, Fuel system · VA · crash

The front camera didn't operate properly The brakes have an elongated stopping distance

Filed Nov 18, 2025 · Body · LA

There is a module that should connect to the hatch door to open. That module in no longer available. Without the hatch door opening, in case of side impact and being pushed into something else, there is no way to get out of the car. This poses a serious safety hazard. I have contacted the Mazda dealership and I am told that the part is "retired" and there is no replacement part at this time.

Filed Jul 18, 2025 · Transmission · NY

I own 2020 mazda cx 30 with 66000 miles. The transmission was shifting with jerky motions. On july 14, 2025 I brought the car to palisades mazda in rockland county new york to have transmission looked at and to change transmission fluid changed. After I dropped the car off later that day I got a call that the transmission was condemned. I looked on the internet with same year make and model and see there is a big problem with the transmissions on these cars and mazda is aware of the problem. Tsb 05-002/20 is a bulletin about transmission failures in this vehicle. Mazda is well aware of the transission problems

Filed Jun 9, 2025 · Seat belts, Transmission · TX

The initial sensor alarm indication was low oil pressure and within less then an hour engine malfunction was detected and the vehicle stopped functioning. This incident occurred on [XXX] in SanAntonio and thereafter it was towed to the Mazda Dealership for inspection upon request. I was driving from Dallas to SanAntonio with my [XXX] and [XXX] children when the vehicle started making strange noise and It the notification on dashboard stated I need to immediately stop the vehicle for safety. Middle of nowhere I had to find a nearest safe place for my children. This vehicle put me and my kids in an unsafe environment due to the faulty engine that was installed by the Mazda company. I was afraid thinking the car will start on fire because it was an engine alert. Yes the vehicle has been inspected by the North Park Mazda dealership on 5/12/25 with an initial quote of engine repair for $7905.88. The first time I noted which was few weeks back prior to this incident when the vehicle stalled at me while I arrived and stopped the vehicle at UT Southwestern Medical Center were I work as a nurse to badge into my parking lot. I got worried for a moment thinking could it be battery issue? I turned off the vehicle and turned it back on and the vehicle starting working. I parked the car and completed a 12 hr shift and thereafter did few weeks of work without any alerts or issue on the vehicle until the day off [XXX]. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

Filed May 17, 2025 · Transmission · GA

I am reporting a repeated and potentially dangerous transmission failure in my 2020 Mazda CX30. At 6 months old, the original transmission failed. Mazda confirmed it was defective and replaced it with a refurbished unit with 10,000 miles on it. That replacement is now also failing—within 4 years of the first failure. This means the car has experienced two transmission failures before reaching 5 years of service. This raises concerns about: •The reliability of Mazda’s factory parts •The quality and safety of refurbished transmissions Mazda uses in warranty repairs •A potential pattern of premature transmission failures on this model Repeated transmission failure can cause loss of power and control, posing serious safety risks to drivers and passengers. Mazda has all service records confirming both incidents. I am submitting this to alert the federal safety agency to a possible defect pattern that may warrant investigation.

Filed Dec 19, 2024 · Electrical · 49,000 miles · GA

The contact owns a 2020 Mazda CX-30. The contact stated that after starting the vehicle, the instrument panel made an abnormal sound. The contact then noticed that the odometer had inadvertently rolled back to 9,999 miles. The vehicle was not diagnosed or repaired by an independent mechanic or dealer. The manufacturer was not made aware of the failure. The failure mileage was approximately 49,000.