MAZDA Complaints

My 2018 Mazda 3 has an intermittent electrical failure on the high-speed CAN network that causes multiple safety-critical systems to fail while driving. When the fault occurs, the dash lights up with warnings for powertrain, ABS/traction, lane departure, collision-avoidance, TPMS, immobilizer, and the check-engine light. The car also hesitates or “lurches” between 15–30 mph during these events. At one point in 2024, the vehicle went into limp mode on the freeway, creating a safety hazard. These failures are intermittent but repeatable. Diagnostic scans from 2023–2025 show multiple U-codes for lost communication between control modules; two later became permanent. The issue appears unrelated to any one component and affects many systems at once. The vehicle has been to every Mazda dealership in the North Texas region (Mesquite, Freeman, Hiley, Norm Reeves, Town North). All performed only basic scans; none completed a full CAN-bus or wiring-harness diagnostic. Town North kept the vehicle for six weeks (Sept–Oct 2025), replaced a coil and spark plugs, performed a camera calibration and a TCM update, but the network failures returned within 38 miles. We sought independent inspection only after dealerships repeatedly refused diagnosis whenever the warning lights were not on at the moment of arrival. In November 2025, a technician found significant internal corrosion inside the negative battery cable; touching the cable reproduced the full failure immediately. The corrosion extends deep into the wire sheathing. This appears to be an electrical defect affecting CAN communication and power/ground integrity. When the fault occurs, multiple safety systems disable at once and the vehicle behaves unpredictably. Mazda Corporate has declined further assistance, and the defect remains unresolved. I am filing this report because this is a recurring safety issue that may affect other vehicles of the same model and year.

The Cyclinder Head cracked. This could cause the engine to fail, and leaving the driver on the highway or other unsafe locations of travel. The certified repair shop along with the insurance adjuster advised it was a manufacturing defect. The warning sign was an oil burning smell inside the vehicle while stationary and inside the garage.

I pulled into the driveway (at about 5 mph) of my passenger's home, when a very loud, metallic pop occurred somewhere inside my vehicle. I could not discern the problem by visually inspecting the car. Upon returning to my home, I arranged for the dealership to inspect the car's suspension. They found that both rear springs had snapped off from their lower vehicle attachment points. At the time of the incident, my car was less than 6 years old and had approximately 62500 total miles. I had the dealership replace both rear springs and associated attachment hardware. Prior to this failure, the dealership had routinely inspected the suspension of my vehicle as part of PA annual inspections. I experienced NO warning symptoms prior to the suspension failure.

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.

i-Stop Malfunction. Engine not restarting after the hybrid system stalls engine at a stop.

Component/System: Automatic transmission (requires full replacement). The vehicle is currently located at Safford Mazda of Fredericksburg, 10653 Patriot Hwy, Fredericksburg, VA, 22408, and is available for inspection upon request. Safety risk: The transmission developed a loud whining and grinding noise while driving, indicating imminent risk of sudden loss of motive power or seizure. This creates a severe crash hazard, especially on highways or during acceleration/merging. Sudden loss of propulsion without warning can leave the driver unable to accelerate, maintain speed, or move out of harm’s way. The problem has been reproduced and confirmed by Safford Mazda (authorized Mazda dealer). On October 16, 2025, they diagnosed the vehicle as requiring a complete transmission replacement (Repair Order/Multi-Point Inspection Video is available). The vehicle has not yet been inspected by the manufacturer, police, or insurance representatives, but remains at the dealership awaiting parts. Starting approximately in late August, a transmission whine started zero warning lights or alerts ever appearing. Noise rapidly worsened. [XXX]: expert friend drove it once, instantly recognized imminent failure, and ordered me to stop driving immediately. At ~20,000 miles, the dealer confirmed the drive unit must be fully replaced, still with no dashboard warning ever triggered. Had I kept driving while trusting the silent system, this critical component could have seized at any moment, causing sudden total loss of propulsion at highway speed or in traffic with my young child on board. The complete absence of any alert during a proven, progressive failure is an urgent, unacceptable safety defect that demands immediate investigation and recall before a family is injured or killed. As of [XXX] , the vehicle has been out of service for 33+ calendar days. The dealer informed me I am #60 in Mazda’s national transmission replacement backlog. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

My rear subframe rusted thru and has holes in it. It is too dangerous to drive and mazda won't recall the rear like the front subframe knowing that a lot of people are suffering from the same issue. A subframe should last a long time. My mechanic inspected the car and feels like it's not safe to drive.

The Infotainment system is cracking uncontrollably and will make the rear view camera unusable and a safety issue. It keeps resetting every minute. Mazda corporation wont pay for the repair that they are charging about 1,000 to fix it.

TSB 02-003/24 Car front suspension bolts corroded and making metal on metal sounds during turning and braking

Radio audio randomly stopped working and you have to disconnect the negative or you have to leave the car off essentially all night. It’s definitely unknown issue there’s videos all over YouTube about it and there’s forms on read about it.