2021 Mazda CX-5

While driving in the Interstate, a truck swerved towards my lane; I swerved into the next lane to avoid the truck hitting me and when I began to swerve my Lane Departure warning malfunctioned and caused my car to completely shut down. I immediately put my hazard lights on to hopefully avoid being hit; but, a car behind plowed right into my rear end. The police were onsite at the accident. My vehicle has been inspected by an independent service center and my insurance representative.

I was sitting at a traffic light with my foot on the brake waiting to turn left onto Lee Highway from Fairfax County Parkway. Car jerked forward TWO times in a row, both times hitting the car in front of me. Our lane was at a dead stop waiting for the left hand arrow. The cars to the right of us had the green and were moving forward. I felt like I had no control over the car during this time.

The vehicle developed an engine oil leak from the timing cover due to what appears to be premature seal failure. Engine oil was leaking externally and could drip onto hot engine components, creating a potential fire hazard while the vehicle is in operation. The leak also increases the risk of low engine oil levels, which could lead to engine damage or sudden engine failure if not detected in time. This issue required an expensive repair despite the vehicle being properly maintained. I have since learned that many other Mazda owners have reported similar timing cover oil leaks on this engine, suggesting this may be a widespread defect rather than normal wear and tear. I am submitting this complaint so NHTSA can evaluate whether this represents a safety-related defect that warrants further investigation.

The vehicle's Connectivity Master Unit (CMU) suffers from a severe, persistent electronic hardware malfunction that causes the central information display and dashboard telemetry to blink, cycle, and drop signals erratically. This specific hardware architecture failure threatens to corrupt data transmission lines directly connected to the Advanced Driver Assistance System (ADAS), creating an imminent safety risk of unintended automatic emergency braking or false sensor deployment during highway transit. The vehicle utilizes the exact same defective CMU hardware component that the manufacturer has acknowledged and recalled on other model cohorts; however, the manufacturer has explicitly excluded this specific VIN from safety recall eligibility. Diagnostic attempts by the authorized dealer network relied solely on forcing digital software updates that completely failed to correct the core hardware signaling instability, leaving the vehicle un-repaired and presenting an active, unmitigated electrical and safety hazard on public roads.

The contact owns a 2021 Mazda CX-5. The contact stated that while driving 70 MPH on the interstate and changing lanes, the blind spot warning light was inoperable. The contact stated that the blind spot indicator then became operable. An independent mechanic was notified of the failure and stated that the repair was not covered. The local dealer was contacted, where a prior unknown diagnostic test was completed; however, the blind spot failure had not been addressed. The vehicle was not repaired. The manufacturer was not contacted. The failure mileage was approximately 95,000.

2021 Mazda CX‑5 (VIN: [XXX] ). First low‑oil warning at 17,800 miles. ([XXX]) Mazda dealership in La Crosse, WI performed an oil change and fully refilled the oil. Second low‑oil warning at 18,700 miles — only 900 miles later. ([XXX]) This indicates rapid, abnormal oil loss consistent with the known valve‑stem‑seal defect for this model year. Sudden low‑oil conditions pose a safety risk due to potential engine damage or failure. Requesting NHTSA document this issue. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

My 2021 Mazda CX‑5 is experiencing excessive oil consumption. The vehicle is burning oil between regular oil changes, and the oil level drops noticeably before the recommended service interval. I have noticed a burning smell and/or signs of oil loss without visible leaks. This raises concerns about potential engine damage, stalling, or fire risk while driving. The issue has occurred repeatedly and does not seem normal for a vehicle of this age and mileage. I am filing this complaint because this may indicate a defect affecting engine safety and reliability.

2021 Mazda CX5 AWD- Non Turbo Engine. Sunny Day, Dry. My Car was clean. No Precipitation. Some shadows of the interstate light poles across the road 200-300 feet in front of me, but they were thin shadows. Sun Was to my Left. I was driving South on May 01 2026 about 10am on the Interstate going Highway Speeds, with adaptive cruise control "on", in the 2nd lane of a 4 lane interstate. Thankfully no other traffic ahead or behind me. Car slammed on the brakes suddenly, pretty hard. I counteracted and added more gas pedal to keep in going. I turned off the Cruise Control. After a while I re-engaged the Cruise Control and had no issues. This could have been a huge accident in busier traffic. Will get the car checked out at Mazda Dealership Service this week.