Open safety recalls, the components owners report failing most often, crash-test results and running costs for the 2021 Mazda MAZDA3, assembled from NHTSA and EPA records.
Everything on this page applies to the model as a whole. Run its VIN to decode that exact car, its engine, trim, assembly plant and factory equipment, alongside these records.
Open a VIN recordRecalls and complaints are filed against a specific model year, so figures differ from one year to the next even within a single generation. See every Mazda MAZDA3 year.
No EPA fuel-economy match for this model. Naming may differ, or it predates EPA records.
The parts named most often across 54 owner complaints filed with NHTSA for this make, model and year.
1 crash · 1 injured
2 fires
Complaints are self-reported and skew toward problems people find alarming, so read this as where to look rather than as a defect rate.
While driving to work, the dashboard displayed “Charging system malfunction, pull over.” The driver pulled over safely. The vehicle has electric power steering, so a loss of charging power while driving could reduce steering assist and cause the vehicle to stall in traffic. This happened three days after a Mazda dealer replaced the front passenger-side lower control arm. That part had failed at 111,777 miles, causing clunking under braking and making the car unsafe to drive (previously reported to NHTSA). This is the second safety-related failure on this vehicle in two weeks. The vehicle is again off the road pending dealer diagnosis. Reported to Mazda Customer Experience, case #00503860.
Vehicle: 2021 Mazda Mazda3 VIN: [XXX] Mileage at failure: 111,777 Date the problem started: [date you first heard the clunk] Location: [town], [XXX] Crash / fire / injury / death: No Was the vehicle moving? Yes Component: Suspension: Front (Lower Control Arm) Description: The front passenger-side lower control arm on my 2021 Mazda3 failed at 111,777 miles. The car began clunking loudly when braking and while driving. My mechanic inspected the car on a lift, identified the lower control arm as the source, and told me the car was not safe to drive. He suspects a failed or defective part. A bolt hole near the rear control arm mount was also found empty, with rust on the threads. The lower control arm holds the front wheel in place and carries the load under braking and steering. A failure like this could cause loss of steering control. The car has been off the road since the failure. I live in [XXX], where roads are heavily salted in winter. Mazda has issued earlier recalls on other models for corrosion in the front lower control arms that could let the ball joints separate. I’m concerned this may be a similar issue. I reported this to Mazda Customer Experience on October 8, 2026 (case number: [number]). The car is scheduled for diagnosis at Thompson’s, an authorized Mazda dealer in [XXX]. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)
Car made grinding sound with notable vibration when starting to move after shifting into drive. Felt like brakes weren't releasing. Had car towed to dealership where they diagnosed that the front left brake shim was damaged and making contact with the rotor, had to pay to fix it out of pocket.
Low engine oil message appeared on dash. Had car towed to Mazda. Had valve stem seals replaced under warranty.
Making sharp right turn out of parking lot under hard acceleration, car suddenly made terrible grinding sound that shook the whole car. Continued driving, within another quarter mile the whole car started shaking again with loud noise. Had car towed to Mazda where they discovered that the rear differential had failed. Rear differential replaced under warranty. Noticed faint high pitched sound coming from rear in months leading up to incident. Had differential and transfer case fluid changed less than 1000 miles and 1 month before incident making me wonder if fluid was underfilled/wrong fluid used or the diff was just bad.
My rear differential case cracked, anytime the four wheel drive system was engaged the entire drivetrain would lock up. Luckily we were only on side roads so going less than 30 mph if we had been on the highway when this happened we could have been in an accident or lost control. The dealer did confirm the problem and it was fixed under an extended warranty. There was no warning just all of a sudden a loud bang and all the wheels locked up. I have a copy of the video inspection done at the dealer if there's anyway to send that. I can get a copy of the repair invoice if needed
At 31,000 miles the control arm lower ball joints are torn on both lower. They must be replaced. This is a safety hazard. This should not be an issue with low mileage on this car.
I was driving when all the sudden there was a loud bang sound. The differential housing cracked. The when awd is demanded the rear diff was was locking up instead of engaging. Luckily we were just on city streets and not on the highway as this rear wheel locking up could cause a crash. Mazda wasn't very helpful with the replacement. Luckily I had a aftermarket warranty but it only paid for a used replacement, which is also failing. I have read lots of stories of this rear differential failure across all types of Mazda's from this era and really wish they would do the correct thing and resolve the problem.
Spontaneous loss of power while driving on highway. Check engine light came on. Speed limited by car. Continues to vibrate especially at idle from cold start. Code P0304 intermittently popping up.
During the incident, the vehicle exhibited an uncontrollable malfunction—the steering wheel suddenly jerked sharply to the right while accelerating violently, leaving me unable to steer or brake effectively, the car was looking forward. The car ultimately came to a stop upon colliding with a truck parked diagonally in front of me. After impact, I observed that the front tires remained stuck in a turned-right position, with the steering wheel also locked in that position. This was not an isolated event. Multiple reports from Mazda owners describe similar experiences with their vehicles unexpectedly veering to the right and accelerating without driver input. Given these recurring reports and my own experience, I strongly suspect that a manufacturing defect—whether mechanical, electronic, or software-related—may have contributed to this accident.
The thermostat malfunctioned on this vehicle, resulting in the thermostat remaining open and providing excess coolant to the engine, which in turn damaged internal components of the engine (compromises safety), decreased fuel economy, increased emissions (compromised safety), and decreased the life of the engine within the vehicle. It is available for inspection upon request. The vehicle has been inspected by an independent mechanic and will be inspected by the Mazda dealership in 7 days. There were no prior warnings until the engine malfunction notice appeared, the vehicle began to make jolts and stuttering sounds, and the temperature gauge within the vehicle failed to rise to optimal range. As this occurred while the vehicle was in use (safety concern), though I was pushing the gas there would be delayed response due to improper temperature, which increased the risk for an accident to occur.
When this feature is left on in my vehicle, it will detect curves, vehicles, and objects that are not there, and as a result, will attempt to turn my steering wheel (safety concern). I have had to keep this feature turned off to prevent it wrecking the car, because I could be on a straight road, and it will detect a curve that isn’t there and begin turning the wheel, which could result in a fatal accident if not corrected and disabled by the driver. It is available for inspection upon request. As the dealer has not driven the vehicle, they have not recreated the error, however if anyone were to drive the vehicle, they would be able to observe the malfunction. The dealer has been made aware on many occasions, though they never documented it and only suggested that I turn the feature off, which automatically turns itself on upon ignition. There are no warnings that there is a malfunction; you only know there is an error once an alert pops up thinking you’re missing a curve and attempts to turn your steering wheel though there is no curve. This issue has persisted over the life of the vehicle.
Showing 12 of 54 complaints.
NHTSA lists 1 recall for this make, model and year. Recalls apply to the model, so some may already be fixed on this specific car. A dealer can confirm from the VIN.
Issue: Mazda North American Operations (Mazda) is recalling certain 2021 Mazda3 and CX-30 vehicles. Air may suddenly leak from the tire air valve.
Risk: A sudden air leak from the tire air valve may cause a loss of vehicle control while driving, increasing the risk of a crash.
Remedy: Mazda will notify owners, and dealers will replace all four tire air valves with new parts, free of charge. The recall began April 6, 2021. Owners may contact Mazda customer service at 1-800-222-5500 Option 4. Mazda's number for this recall is 4721B.
Campaign 21V101000
Rated configuration: 2021 Mazda Mazda3 5 HB AWD