2020 Mazda CX-30

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.

NHTSA ID

11769418

Incident

Oct 6, 2026

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.

NHTSA ID

11761957

Incident

May 1, 2026

The front passenger side headlight is making a whirring noise whenever the light is turned on. Based on the NHTSA 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.

NHTSA ID

11751262

Incident

Jul 13, 2026

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 NHTSA 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

NHTSA ID

11710048

Incident

Dec 30, 2025

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

NHTSA ID

11702067

Incident

Apr 5, 2025

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.

NHTSA ID

11700042

Incident

Jan 1, 2024

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

NHTSA ID

11674592

Incident

Jul 14, 2025

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)

NHTSA ID

11665901

Incident

May 2, 2025

Subject: Update – Campaign Warranty Claim Response Enhancements – Modules Not Repaired for Certain Campaigns Dear Mazda Dealer Colleagues, On October 28, 2026, a change was implemented in the warranty claim response screen to provide precise information for all campaigns requiring module programming or module replacement subject to the LECS system software checks. As previously announced, some claims were automatically rejected with the Edit code JN1 – One or More Modules Are Not Updated when submitting a campaign warranty claim. This response was based on the session file received from MDARS or MDARS II at the dealership and the VIN on the claim submitted. This change provides additional Related Information which enhances the edit code information. This information allows the dealer to correct the error without contacting Warranty or Hotline. Edit code JN1 now contains the actual module name and the software version that was collected from the car and what the minimum required software needed to be for the claim. Using this information, the technician can now identify the exact error or errors and correct the concern.

Some customers may complain about any of the following 1. Infotainment Center Display does not provide the Authorization Code (OTP) during the MyMazda App Connected Vehicle enrollment. 2. Remote function(s) inoperative.

Mazda Connected Services - Frequently Asked Questions (FAQ) This Service Alert supersedes the previously issued SAs listed below. The changes are noted in Red text. SA-042/26 06/30/26 DESCRIPTION Frequently Asked Questions (FAQ) Index General Questions MAZDA CONNECT Indication Setup and Getting Started Dealer Processes Registration / Enrollment / Take-Over Customer Subscription Status WI-FI General Informatio Opening the TCU Communication Line WI-FI How-To Conditions for Remote Engine Start Will Not Function WI-FI Trial Period Conditions for Remote Engine Start Function Will turn engine OFF Interacting With The App TCU Communication Line Status Service Issues Educational Videos Troubleshooting Resources MyMazda App Error Codes Customer Opt-Out

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

This Service Alert supersedes the previously issued service alert listed below. The changes are noted in Red text. SA-038/26 08/18/26 and 06/15/26 DESCRIPTION Some customers may complain about any of the following: 1. Infotainment Center Display does not provide the Authorization Code (OTP) during the MyMazda App

This Service Alert supersedes the previously issued service alert listed below. The changes are noted in Red text. SA-038/26 06/15/26 DESCRIPTION Some customers may complain about any of the following: 1. Infotainment Center Display does not provide the Authorization Code (OTP) during the MyMazda App Connected Vehicle enrollment. 2. Remote functions inoperative. Engine Start / Stop Door Lock / Unlock Lights ON / OFF Climate Control 3. MAZDA CONNECT connected vehicle reception strength icon shows "X" or " ". Index MAZDA CONNECT 2 Center Display Status Icon MAZDA CONNECT 3 Center Display Status Icon Remote Engine Start Will Not Function Remote Engine Start Function Will turn engine OFF Customer Subscription Status TCU Communication Line Status