2021 Mazda CX-5 Complaints

ELECTRICAL SYSTEM,FORWARD COLLISION AVOIDANCE — Filed 06/03/2026

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.

LANE DEPARTURE — Filed 06/20/2026

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.

ENGINE,FUEL/PROPULSION SYSTEM — Filed 05/05/2026

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)

ENGINE — Filed 05/10/2026

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.

VEHICLE SPEED CONTROL,SERVICE BRAKES,FORWARD COLLISION AVOIDANCE — Filed 05/01/2026

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.

SERVICE BRAKES — Filed 10/02/2023

The car has 21000 miles and is driven lightly when applying the brakes the steering wheel started shaking and the car made noises - the brakes could have failed at any time and at any speedl The dealer said the rotors were warped. no warning and no notification from the manufacturer that this could happen at such low miles. i didnt bring the vehicle in because i could not believe the brakes would be at fault with such low miles - it started at 10000 miles. a notification from the manufacturer or dealers would prevent a catastrophic brake failure

ENGINE — Filed 08/09/2025

Due to oil consumption issues & oil leak on 2021 Mazda cx 5 AWD I was told the timing cover and gasket needs replacement due to oil leakage. This appears to be a very common issue with this vehicle. The engine is at risk of catastrophic failure due to low oil levels

ENGINE,FORWARD COLLISION AVOIDANCE — Filed 03/08/2026

The contact owns a 2021 Mazda CX-5. The contact stated that while driving at an undisclosed speed, the Forward Collision Avoidance Automatic Emergency Brakes activated unintendedly, and the vehicle jerked to the left and independently accelerated and moved back in the lane intended lane. The vehicle then jerked to the right, unintendedly accelerated, and then went back into the intended lane. Then the vehicle resumed normal operation. While driving approximately 60-65 MPH a week later, the vehicle started jerking. The “Smart City Brake Malfunction” message was displayed, and the engine warning light was illuminated. The local dealer was not contacted. The vehicle was not diagnosed or repaired. The manufacturer was not notified of the failure. The failure mileage was approximately 114,000.

ENGINE — Filed 03/04/2026

The contact owns a 2021 Mazda CX-5. The contact stated that while driving at an undisclosed speed, the low oil warning light illuminated. The vehicle was taken to the dealer however, the vehicle was not diagnosed or repaired. The contact was advised by the dealer to continue adding oil to the engine as needed. The manufacturer was made aware of the failure. The approximate failure mileage was 46,465.

TIRES — Filed 05/01/2025

The contact owns a 2021 Mazda CX-5 equipped with Firestone Tires, Tire Line: Destination LE3, Tire Size: 225/55/R19, DOT Numbers: 17XEFLE320725 and 17XEFLE321524. While the vehicle was parked, the contact was informed by a co-worker that there was a bubble on the rear passenger's side tire. The contact inspected the tire and noticed that there was a bubble that was two inches deep and 3 inches long on the side wall of the tire with DOT Number: 17XEFLE321524. The vehicle was taken to Tire Plus, where the tire was replaced. Additionally, the contact stated that while driving at 70 MPH, there was an abnormal popping sound heard, and the TPMS warning light illuminated. The contact was able to pull over to the side of the road. The vehicle was towed to the residence. The contact noticed that there was a 2-inch long crack in the tread of the rear driver's side tire, the tire with DOT Number: 17XEFLE320725. The tire was replaced with the spare tire. The vehicle was then taken to Tire Plus, where the contact was awaiting the tire replacement. The tires were replacement tires. The manufacturer was not notified of the failures. The tire failure mileage was approximately 15,000. The vehicle failure mileage was approximately 64,000. The VIN was not available.