Au7o mascotAu7o
Known IssuesTest Hub demo
  1. Au7o
  2. /
  3. Known Issues
  4. /
  5. Mazda
  6. /
  7. Mazda3
Mazda · Known Issues

2020 Mazda Mazda3 Problems: 3 Known Issues

2020 model year · NHTSA recalls, manufacturer TSBs, and owner forum reports · Updated September 2026

Share:@au7o.io

2020 · All trims · All engines

Choose the year and equipment for your written issues and visual request.

Known IssuesMotorcycle IssuesDTC LookupDrivePricingAboutTermsPrivacyCookiesConsentData rightsCopyrightFeedback
Share:@au7o.io

Vehicle data and repair guidance on this site are compiled with AI assistance and may contain errors. Always verify with your service manual or a qualified mechanic.

Data protection representation

DataRep representative in the United KingdomDataRep representative in the European Union
Au7o · 2026
Built for DIY mechanics. Privacy-first.
Explore free Hub demo
No email neededHow interest is saved

Interest applies to the selected vehicle and configuration; it is not a reservation. Voting stores a first-party identifier for up to 180 days to prevent repeat votes. No account or email is needed. Clearing cookies or using another device may count separately. Privacy

Visual coming soon

Your interest helps us choose what to build next.

Visual Known Issues · Coming soon

$4.99/month plus taxes at launch · No payment today

Preview the XT6 example
Issue summary

According to Au7o's research across NHTSA recalls, manufacturer TSBs, and owner forum reports, the 2020 Mazda Mazda3 has 3 documented known issues, with 1 rated critical. The most serious is 2019-2020 Mazda3 Smart Brake Support False Activation - Unwanted Emergency Braking (Recall 19V907 / 4219L) ($0-$0 repair). Across all issues with published estimates, repair costs range from $400 to $1,000. DIY maintenance guides at au7o.io.

In This Article

  • Mazda3 Safety/Recalls1
  • Mazda3 Electrical1
  • Mazda3 Body/Panels1
  • Recalls4
  • FAQ
Get Started
Back to top

In This Article

  • Safety/Recalls1
  • Electrical1
  • Body/Panels1
  • Recalls4
  • FAQ

All 3 Known Issues

Filter:
ALL YEARS2025202420232022202120202019201820172016201520142013201220112010200920082007200620052004

On the 2019-2020 Mazda Mazda3, incorrect programming in the Smart Brake Support (SBS) control software on early BP-generation Mazda3s causes the forward-sensing system to falsely detect an obstacle where none exists - commonly triggered by overhead signs, bridge shadows, guardrails or steam. The automatic emergency braking then fires at speed, complete with the collision warning chime and warning message, slowing or stopping the car with no vehicle ahead. Mazda recalled approximately 35,390 US Mazda3s under NHTSA campaign 19V907000 (Mazda recall 4219L); NHTSA's complaint database contained a crash and an injury tied to unintended braking on 2019 cars.

Common Symptoms

  • Vehicle brakes hard by itself with no obstacle present
  • Collision warning chime and warning message with nothing ahead
  • Sudden deceleration under overpasses or near roadside signs
  • Risk of being rear-ended after an unprompted stop

How to Fix

Have the dealer perform recall 4219L / NHTSA 19V907 - the SBS control software is reprogrammed free of charge, and vehicles in certain production date ranges also receive an instrument cluster software update or cluster replacement plus a revised owner's manual. If false activations continue after the recall, have the front camera/radar sensor aim and windshield calibration checked, especially after any windshield replacement. Disabling SBS from the settings menu is only a stopgap.

Typical repair cost:$0 - $0

Research This Issue

GoogleRedditYouTubeNHTSA
Community Reported
High ConfidenceVerifiedReviewed Aug 2026

On the 2019-2022 Mazda Mazda3, mazda published separate service paths for some 2019-2022 Mazda3 Mazda Connect complaints. Bulletin 16-001/23 covers a defined set of software symptoms on specified non-turbo VIN and production ranges, including a black or frozen display, rebooting, switch or audio-control faults, Bluetooth/USB/CarPlay/Android Auto problems, and certain camera-display behavior. Bulletin 16-004/23 covers a narrower blank-screen or slow-restart condition caused by a defective CMU circuit-board element (DRAM) on specified vehicles built before December 1, 2021. These bulletins do not establish that every 2014-2022 freeze is worn eMMC storage or that one replacement CMU fits every vehicle.

Common Symptoms

  • Center display freezes, turns black or white, or reboots
  • Mazda Connect is blank or unusually slow to restart after vehicle startup
  • Bluetooth, USB, CarPlay, Android Auto, audio controls, or camera display misbehaves in a way listed by the software bulletin

How to Fix

Record the exact symptom and when it occurs, preserve infotainment DTCs, and have a Mazda technician verify the VIN, build plant/date, turbo applicability, installed software, CMU part number, and CMU serial number. If bulletin 16-001/23 applies, update Mazda Connect to the latest Mazda-authorized software and verify the symptom. For the blank-screen or slow-start condition in bulletin 16-004/23, replace the CMU only when its part and serial number fall in Mazda's affected ranges, then update the replacement as directed. If neither bulletin applies, follow Mazda's symptom diagnosis rather than ordering a used or generic CMU from this card.

Owner tips & cautions

  • TipPhotograph the software version and record the VIN, build plant/date, exact symptom, connected device, and any infotainment DTC before service; Mazda's paths depend on those details.
  • WarningDo not buy a CMU from a generic model-year search. Mazda requires the installed CMU part and serial number to be checked, and many documented symptoms are software rather than failed hardware.

Research This Issue

GoogleRedditYouTubeNHTSA
Manually Verified
High ConfidenceVerifiedReviewed Jul 2026

On the 2019-2025 Mazda Mazda3, fourth-generation Mazda3 (BP) owners report an unusually high rate of windshield stress cracks that appear without any visible impact point. The cracking typically originates from the edges of the windshield, often near the A-pillar or bottom edge, and spreads across the glass. The issue may be related to the windshield's steep rake angle, body flex, or manufacturing tolerances in the glass bonding process.

Common Symptoms

  • Crack appears on windshield with no impact point
  • Crack starts from edge of windshield
  • Crack appears after temperature change
  • Progressive crack growth over days
  • Multiple windshield replacements needed

How to Fix

Replace the windshield. File an insurance claim as stress cracks are typically covered under comprehensive coverage. Some owners have successfully had Mazda cover the replacement under goodwill warranty, especially if the crack appears with no impact point on a low-mileage vehicle. Use OEM glass to ensure proper fit with the rain sensor, HUD (if equipped), and ADAS camera calibration.

Typical repair cost:$400 - $1,000

Research This Issue

GoogleRedditYouTubeNHTSA
Community Reported
Medium Confidence
NHTSA Recalls4 recalls

AIR BAGS: AIR BAG/RESTRAINT CONTROL MODULE:SOFTWARE

Mazda North American Operations is recalling certain 2024-2025 Mazda3 and CX30 vehicles. The Sophisticated Air Bag Sensor (SAS) units may set an error code and deactivate the air bags, due to a low battery condition.

Campaign #25V35700029/05/2025

BACK OVER PREVENTION: SENSING SYSTEM: CAMERA

Mazda North American Operations (Mazda) is recalling certain 2024 CX-90 and MAZDA3 vehicles. Due to a software error, the rearview, front, and/or side camera images may not appear on the display. As such, these vehicles fail to comply with the requirements of Federal Motor Vehicle Safety Standard number 111, "Rear Visibility."

Campaign #23V71800026/10/2023

LANE DEPARTURE: SENSING SYSTEM: CAMERA

Mazda North American Operations (Mazda) is recalling certain 2024 Mazda 3, CX-30, and 2025 CX-50 vehicles. A malfunction in the forward sensing camera (FSC) may prevent the automatic emergency braking system and the lane-keep assist system from functioning. In addition, the headlights will not automatically adjust from high beams to low beams as intended.

🔧
A mechanic who knows YOUR exact car
Answers tuned to your year, make, model & trim — not generic advice. Save your garage so it always has the right context.
Get ahead of Mazda Mazda3 problems — free
Leave your email and we'll alert you the moment there's a new recall or known issue for your Mazda Mazda3. Free, no account needed.

Don't see your problem? Describe your symptoms to get a diagnosis, or get a full repair guide.

Other Mazda Models

Mazda CX-530Mazda CX-6027Mazda CX-5026Mazda MX-5 Miata22Mazda MX-621Mazda CX-7019

Frequently Asked Questions

What are the most common Mazda Mazda3 problems?

According to Au7o's research across NHTSA recalls, manufacturer TSBs, and owner forum reports, the 2020 Mazda Mazda3 has 3 documented issues. The most frequently reported are: 2019-2020 Mazda3 Smart Brake Support False Activation - Unwanted Emergency Braking (Recall 19V907 / 4219L), 2019-2022 Mazda3 Mazda Connect Blank Screen, Freeze, or Reboot, Windshield Spontaneous Stress Cracking. Of these, 1 is rated critical and should be addressed promptly.

Is the Mazda Mazda3 reliable?

The 2020 Mazda Mazda3 has 3 known issues compiled from NHTSA recalls, manufacturer TSBs, and owner forum reports. 1 issue is rated critical: 2019-2020 Mazda3 Smart Brake Support False Activation - Unwanted Emergency Braking (Recall 19V907 / 4219L). Prospective buyers should inspect for these issues and factor potential repair costs into their purchase decision. Regular maintenance following the manufacturer's schedule helps prevent many common problems.

How much does it cost to fix common Mazda Mazda3 problems?

Repair costs for known Mazda Mazda3 issues range from $0 to $1,000, depending on the specific problem and whether you choose DIY or professional repair. The most critical issue, 2019-2020 Mazda3 Smart Brake Support False Activation - Unwanted Emergency Braking (Recall 19V907 / 4219L), typically costs $0-$0 to repair. Au7o provides step-by-step DIY maintenance guides that can help reduce repair costs.

What is the 2019-2020 Mazda Mazda3 2019-2020 Mazda3 Smart Brake Support False Activation - Unwanted Emergency Braking (Recall 19V907 / 4219L)?

Incorrect programming in the Smart Brake Support (SBS) control software on early BP-generation Mazda3s causes the forward-sensing system to falsely detect an obstacle where none exists - commonly triggered by overhead signs, bridge shadows, guardrails or steam. The automatic emer… Repairs typically run $0-$0. Severity: high.

What is the 2019-2022 Mazda Mazda3 2019-2022 Mazda3 Mazda Connect Blank Screen, Freeze, or Reboot?

Mazda published separate service paths for some 2019-2022 Mazda3 Mazda Connect complaints. Bulletin 16-001/23 covers a defined set of software symptoms on specified non-turbo VIN and production ranges, including a black or frozen display, rebooting, switch or audio-control faults… Severity: medium.

Content on this page was compiled with AI assistance using NHTSA complaints, TSBs, owner reports, and public automotive data. While we strive for accuracy, this information may contain errors. Always verify repair procedures and specifications with your vehicle's service manual or a qualified mechanic.

Data compiled from NHTSA recalls, manufacturer TSBs, automotive forums, and AI-assisted research. No aggregated owner-report counts available for this vehicle yet.

Campaign #24V64900003/09/2024

TIRES:VALVE

Mazda North American Operations (Mazda) is recalling certain 2021 Mazda3 and CX-30 vehicles. Air may suddenly leak from the tire air valve.

Campaign #21V10100022/02/2021

Enter your VIN at NHTSA.gov to check recalls specific to your vehicle.

What is the 2019-2025 Mazda Mazda3 Windshield Spontaneous Stress Cracking?

Fourth-generation Mazda3 (BP) owners report an unusually high rate of windshield stress cracks that appear without any visible impact point. The cracking typically originates from the edges of the windshield, often near the A-pillar or bottom edge, and spreads across the glass. T… Repairs typically run $400-$1,000. Severity: low.