2019 Mazda MAZDA3 Problems

What owners report

Owners of this model year most often describe the automatic emergency braking system engaging when nothing is in front of the car, sometimes at speed, and repeated dashboard warnings that driver-assist features have been disabled. Many complaints are filed at low mileage, in the first few thousand miles of ownership, and several are about noise, fluid leaks, or electronic glitches that appeared gradually rather than after a crash.

1. 1
   Forward collision avoidance

   Automatic emergency braking engages with no obstacle

   Mentioned in 13 of 60 sampled complaints

   Owners describe the car braking hard on its own on clear roads, highways and parking lots, with no vehicle ahead and no warning; several say the car behind nearly hit them. Some had the Smart Brake System recall remedy applied and report the behavior continued. Complaints also describe cruise-control and radar systems dropping out with warnings that safety and driver-support systems are disabled, and dealers often said they could not duplicate the problem. Mostly reported under about 15,000 miles, with several under 1,500 miles; some owners mention rain or recent snow, and a few note the behavior continued after the recall repair.

   Recall 19V907000

   What to check: Ask whether the Smart Brake System recall (19V907000) was performed and whether the owner noticed unexpected braking after it. During a test drive, note any brake warning lights or driver-assist messages.

   2 excerpts from owner complaints in NHTSA records

   “The smart brake system is malfunctioning. The car slams on its brakes for no reason. No vehicle is ahead of me. I have been driving at highway speeds when this occurs and I haven't been rear ended yet. It's happened numerous times before and after I completed the recall. The condition is worse when it's raining. The car has been at the dealership for over 30 days unable to repair.”

   NHTSA complaint #11364488, filed 2020-10, 400 miles

   “Automatic break system malfunctions often and does a hard break. Also the perimeter sensor gets disabled numerous time out of blue while driving and stop functioning until the car restarts. The break happens without any prior indication or same situation. It just happens on the regular road as well as highway. But the highway just scares me. But there is no way I can tell Mazda with a proof.”

   NHTSA complaint #11290226, filed 2019-12, 5,200 miles
2. 2
   Electrical system

   Driver-assist systems disable themselves at random

   • 30 complaints (41%)
   • median 5,000 mi at 1.0 yrs old (17 state mileage)
   • 3 mention a crash, fire or injury
   • filed 2019–2026

   Complaints describe messages such as 'safety and driver support systems partially disabled' appearing while driving, with blind-spot monitoring, lane departure warning and radar cruise control dropping out until the car is restarted. Some also report the instrument cluster flashing, dimming speedometer readings in hot weather, or the car refusing to start with the panel blinking. Dealers reportedly could not reproduce the faults or told owners to cool the cabin. Often reported in the first few thousand miles, in some cases after a short drive in sunlight or heat; a few appear at 15,000-36,000 miles.

   Recall 19V3630002 related service bulletins

   What to check: Ask whether any dealer visit addressed warning lights or network/electric faults, and start the car a few times to watch the instrument panel for flashing or hesitation.

   2 excerpts from owner complaints in NHTSA records

   “Automatic light malfunctions when the car is parked outside under the broad day light. When automatic light malfunctions, the head light turns on automatically and dash meter lighting dims automatically. When the dash meter dims, I can not see the speed or anything within the meter. Have talked to Mazda and stated that I need to turn on an A/C to cool the system down. It is very dangerous that I can not see the speed meter. It has happened few times.”

   NHTSA complaint #11323384, filed 2020-05, 5,000 miles

   “My car suddenly made a big clunk noise and I was warned of a power steering malfunction. I have also been warned multiple times that due to a malfunction the 'safety systems have been disabled', another issue in having is a headlight malfunction. When the headlight malfunction occurs the digital speedometer gets very dark and I am unable to tell how fast I am going. There is no way to turn the brightness up to see the speedometer again until the error code goes away. …”

   NHTSA complaint #11241916, filed 2019-08, 5,000 miles
3. 3
   Transmission and drivetrain

   Jerky or delayed acceleration from a stop

   Mentioned in 7 of 60 sampled complaints

   Owners describe a lag or lurch when pulling away from a full stop or in slow stop-and-go traffic, with the car sometimes feeling like it loses power or goes into a limp mode. Several say the dealer acknowledged the behavior but could not repair it, and some describe more serious loss of motive power with a network malfunction warning. Complaints also mention rough shifts and, in one case, a transmission replaced under warranty. Commonly reported between about 2,000 and 15,000 miles, often in low-speed stop-and-go or uphill driving.

   Recall 19V4970001 related service bulletin

   What to check: Test drive from a complete stop several times and on a slight incline to feel for hesitation or shudder; ask whether the PCM software update from recall 19V497000 was applied.

   2 excerpts from owner complaints in NHTSA records

   “From a full stop, vehicle lags or lurches from takeoff when you hit the accelerator. This is a known problem by Mazda on this vehicle (gen 7) after 3000 miles or more. When I hit the accelerator (especially on a new car), I expect it to go. This lag in moving off the line can be dangerous, in my opinion, but apparently not in Mazda's. …”

   NHTSA complaint #11318310, filed 2020-03, 10,000 miles

   “Automatic transmission went out on me while driving on road. The transmission started to slip while I was doing 15 MPH and just gave out in the middle of the street. All you could smell is burnt fluid and hear a loud whining noise from under the car while at idle. The car only has 12,680 miles on it. The transmission was replaced under warranty. I am highly disappointment with this car.”

   NHTSA complaint #11326012, filed 2020-05, 12,680 miles
4. 4
   Other or unknown

   Airbag system malfunction warning

   • 9 complaints (12%)
   • median 1,500 mi at 0.6 yrs old (3 state mileage, few)
   • filed 2019–2026

   Owners report a dashboard message that the airbag system has malfunctioned, appearing intermittently and sometimes only with a passenger aboard. Complaints describe dealers explaining it as a known harness or connector issue on the seat airbags, with at least one owner noting spontaneous deployment of the curtain airbags. Others report the seat belt no longer retracting. Reported across a wide mileage range, from a few hundred miles to higher-mileage cars; some notices appear during a normal commute rather than after an event.

   1 related service bulletin

   What to check: Turn the ignition on and confirm the airbag light goes out; sit in the passenger seat and ask the owner whether the warning has a history. Ask whether the seat-side airbag harness was inspected or repaired.

   2 excerpts from owner complaints in NHTSA records

   “Got alert regarding air bags while driving. Also rear mirror fell off the plastic casing while driving on freeway. They both happened at different instances. But both happened when I was driving freeway and scared me. Took into Mazda dealer and they said that both were known issue and airbag issue is unannounced recall.”

   NHTSA complaint #11209904, filed 2019-05, 1,500 miles

   “Suddenly there was a error saying airbag system has malfunctioned in the middle of my commute. And it has been reoccurring. And I haven't heard a peep from the dealer.”

   NHTSA complaint #11231363, filed 2019-07, 2,000 miles
5. 5
   Engine

   Oil leaks and coolant system faults

   • 9 complaints (12%)
   • median 336 mi at 0.8 yrs old (1 states mileage, few)
   • filed 2019–2024

   Complaints describe oil leaking onto hot engine parts, low-oil warnings and steam, with owners citing a cylinder head or gasket area as the source. Others report the coolant control valve sticking open, leaving the engine slow to warm and the heater weak in cold weather, and one owner describes the low-pressure and high-pressure fuel pumps being replaced. Dealers in several cases required a specific diagnostic code before acting. Mostly reported between roughly 15,000 and 59,000 miles, and the coolant-valve complaint appears in cold-weather use.

   4 related service bulletins

   What to check: Check for an oil smell or residue around the engine and exhaust, look at the coolant level, and ask whether the coolant control valve or any engine oil-leak repair has been done.

   2 excerpts from owner complaints in NHTSA records

   “I had an oil change back in April of 2024. I have been driving the last couple of days and after about 15 minutes my low oil light comes. this car has 58.800 miles on it. I stopped at a oil express to see if I was low on oil but they said I was at full. I also checked to see if they saw anything leaking but they also said they didn't see anything. if the gasket is bad 58,000 that is telling me it's a faulty product. I'm afraid that my engine could lock up on the highway and cause a bad accident.”

   NHTSA complaint #11592585, filed 2024-06

   “I noticed oil was leaking and my engine was steaming after driving. My mechanic found a crack in a cylinder after watching YouTube and finding out Mazda has this issue.”

   NHTSA complaint #11580786, filed 2024-04

Buying note. Check for a completed Smart Brake System recall remedy and drive the car in traffic to see whether the braking or driver-assist warnings misbehave, since those are the most frequently reported complaints. A pre-purchase inspection covering engine leaks, coolant operation and transmission behavior from a stop is worthwhile.

Summary written with AI from a sample of 60 NHTSA complaints for this model year (picked at random, with complaints that state a mileage and recent ones taken first), then checked automatically against the source records. Where a problem shows a complaint count, every complaint for this model year was matched with fixed keyword rules (written with AI and tested against the sample), and the mileage, age and repair figures are calculated from those complaints; owners' figures are as stated, not verified. Other counts refer to the sample. The excerpts come from NHTSA's public complaint records and are unverified; capitalisation is normalised, NHTSA staff notes are removed, and shortened text ends with “…”. Something wrong? Request a correction.