19V-425
Lug nuts on all four wheels may loosen — a wheel can detach
2019 Mazda3, 25,003 units. The lug nuts on all four wheels may loosen, and a wheel separating from the car is the most serious failure on this page. Dealers tighten the front and rear lug nuts to specification at no charge; Mazda calls this recall 3519F and it began 2019-07-09. It is a short free job, so most cars have had it, but it is also the one campaign here whose consequence is structural — confirm the completion by VIN rather than assuming.
19V-907
Smart Brake Support may brake for an obstacle that is not there
2019-2020 Mazda3, 35,390 units. The forward-sensing system can falsely detect an obstacle and trigger automatic emergency braking, stopping the car suddenly in traffic. Dealers update the SBS software, and some cars also get an instrument-cluster software update or replacement and a revised owner manual, all at no charge; Mazda calls it 4219L. Worth raising specifically on a test drive, because an owner who found the braking unnerving may have switched the system off rather than had it updated.
19V-497
Powertrain control module software error can stall the engine
2018-2019 CX-5, 2018-2019 Mazda6 and 2019 Mazda3, 262,220 units — the largest population of the six. A software error in the powertrain control module can stall the engine. Dealers reprogram the PCM at no charge; Mazda calls it 3719F. A dealer reprogramming leaves a service record behind, which is the difference between this and an over-the-air fix: here there is something to look for in the history.
19V-363
Passenger airbag-off light and seat-belt indicators programmed wrong
2019 Mazda3, 17,016 units. Incorrect programming can switch off the passenger airbag deactivation light while the airbag is actually off, and can switch off the seat-belt indicators while belts are unfastened — so the car can imply a front child seat is safe when it is not. Dealers replace the passenger airbag and seat-belt status indicator assembly at no charge; Mazda calls it 3319E. The remedy is a part rather than software, so a record exists for it.
19V-514
Front seat cover can block the head-restraint lock release
2019 Mazda3, 9,430 units. Seat cover material can interfere with the head restraint lock release button so the restraint may not lock in place, which raises injury risk in a crash. Dealers install spacers under the lock release buttons on both front seats at no charge; Mazda calls it 3819F. This is the one item on the page you can check yourself in the car park — raise each front head restraint and confirm it locks at height.
19V-558
Interior rearview mirror can detach from its housing
2019 Mazda3 with manual dimming mirrors, 22,571 units. The adhesive bonding the interior rearview mirror to its housing may not be properly bonded, letting the mirror come away and cutting rearward visibility. Dealers replace the mirror assembly at no charge; Mazda calls it 3919G. Only cars with the manual dimming mirror are in scope, so an auto-dimming car is out — another case where the option list rather than the model year decides.