2020 Mazda 5: What to check before buying

The touchscreen registers phantom touches. It changes screens, raises the volume to maximum, places calls and drops navigation while driving, and the knob and buttons can stop responding. Software updates often do not fix it, and some owners pay for a new screen. Other reports describe batteries that drain repeatedly, forward camera warnings that disable the driver-assist systems, and dash lights that cut out. In one hospitalization, the engine kept running in a garage after being switched off. In one crash report, the brake pedal would not move and the steering stopped responding.

Automatic emergency braking engages when nothing is ahead. It slams the car to a stop in slow traffic, on clear town streets around 35 mph, and when a car in the next lane passes. Drivers describe near rear-end collisions and passengers thrown forward. Dealers often cannot reproduce the fault. Some reports describe a failed front radar sensor that disables collision warning and radar cruise control. In one crash, the car sped up again after the driver tapped the brake to cancel adaptive cruise, and it sideswiped a truck.

Most reports describe the automatic braking system braking hard with no car ahead. The car shows BRAKE warnings, and drivers behind have to stop suddenly. One driver reports neck and back pain. Two crash reports say the car did not stop when the brakes were applied while parking. In one injury report, the car rolled backward while in Park and the open door ran over the owner. Other complaints include an ABS light with brake lockup and stalling at about 2,000 miles, and grinding noises needing new brakes and calipers at 32000 miles.

The low oil light comes on before the scheduled oil change, and some owners suspect the engine is burning oil. Oil leaks from the timing cover, oil pan gasket and seals are common, and one report describes oil reaching a spark plug. One owner reports a cracked cylinder head above the exhaust manifold, with burning oil and smoke in the cabin. Less common reports include idle speed swinging while stopped at a light, a whoop sound at idle that dealers cannot explain, a faulty thermostat, and an engine that keeps running after shutoff.

The transmission chirps on the 3rd-to-4th upshift or when accelerating gently at 20 to 35 mph. Dealers diagnose a failing torque converter, metal debris inside the transmission, or a transaxle that needs replacing. Onset is usually between 32,000 and 61,000 miles, often with jerking. Help with costs varies: one owner got partial coverage, while others were told their VIN was not covered. Other reports describe a cracked cylinder on a non-turbo engine at 34,000 miles costing over $7,000, oil consumption, and a limp-mode event that stopped the car.

Strong crosswinds at highway speed cause a loud screech or howl from the doors, and dealers often cannot reproduce it. Water leaks come in through the driver door window and the windshield. In one case the windshield leak blocked the driver's view. Sunroofs shatter outward while driving with no visible impact. Owners also report paint chipping on the hood in the first year. A power liftgate opens by itself and was damaged by a closing garage door. One crash report blames a failed rear camera and warning system.

The car surges forward on its own at low speed, while parking, in a drive-thru, or after being parked. Drivers say braking did not stop it. Two crash reports describe hitting a building and a pole, with one injury and one vehicle declared a total loss. Brake system and camera malfunction messages appeared after one collision. A separate report says the cruise control buttons on the steering wheel are not lit, which led a driver to raise the speed by mistake at night.

Passenger-side curtain airbags deploy on the highway with no collision. The bang is loud enough to leave ears ringing, and the deployed bags block the side windows and mirrors while traffic is alongside. Dealers find no system fault. In another report, the driver-side airbags fired after a tire blowout and the car shut off. One crash report with an injury says the airbags did not deploy when the car hit a guardrail and scraped along it.