2022 Mazda 5: What to check before buying

Headlights develop a loud whine, hum, or grinding noise. It can continue for a few minutes after the lights shut off. Dealers trace it to the cooling fan motor inside the LED headlight assembly, and owners say debris from manufacturing wears out the fan bearings. A failing fan can let the lamp overheat and burn out. The noise usually starts between about 29,000 and 41,540 miles, often just after the warranty ends. The fix is a full headlight assembly, which owners say costs $2,500 or more. A few also report dim or uneven beams.

"Air Bag System Malfunction" warnings show up on the dash and in the phone app. They often start in the first few thousand miles, sometimes right after a seat adjustment. Owners cite a service bulletin that points to the wiring harness for the side airbag in the seat. Many need repeat dealer visits. Other reports describe the passenger airbag-off light staying on with an adult in the seat and curtain airbags going off without a crash. In two crashes that caused injuries, the airbags did not deploy.

Batteries go dead after the car sits for a few days. Some owners now carry a jump pack after several battery replacements. Dealers blame a constant power draw or a faulty battery. Other reports describe critical malfunction alerts, internal network faults, and sudden loss of power on the highway with the check engine and battery lights on. Two complaints involve fire, including a heated windshield element that smoked and cracked the glass. Repairs to airbag wiring under the seat are also logged here, with owners waiting weeks for parts.

Transmissions fail in several ways. Automatics refuse to move in gear or rev above 5,000 RPM, and the failures come back after valve body replacements and even a full transmission swap. Manual gearboxes grind on downshifts as the synchronizers wear, with grinding reported around 20,000 miles. Other complaints cover a failed transfer case on an almost-new car, a cracked cylinder head spraying oil, a leaking timing chain cover gasket, and a rear whine at highway speed. Most of these failures come with no warning light.

Cold starts bring a sharp metallic ticking that owners link to the hydraulic valve lash adjusters. A service bulletin covered this problem on earlier model years. Some engines burn enough oil between changes to trigger a low-oil warning, and dealers find no leak. More serious reports describe a cracked cylinder head that leads to overheating, smoke from the engine bay, and a pull-over-immediately alert. Owners also report a coolant control valve stuck open and a warranty extension notice for a thermostat that can fail in the open position.

Automatic emergency braking fires with nothing ahead and brings the car to a full stop. Owners report it on highways, in intersections, and in slow traffic. The alert often sounds at the same moment the brakes slam on, so the driver gets no advance warning. Dealers often cannot reproduce the fault. Two complaints involve crashes. In one, a false stop led to the car being hit from behind. In the other, the system gave no warning and added no braking before impact.

Engine RPM surges while the car is stopped or slowing down, and the car lurches forward against the brake. One report blames this on a large shoe pressing both pedals at once. A separate complaint describes a transmission control unit fault with code P061B that five repair attempts failed to fix. The main risk is the car moving unexpectedly near an intersection or over a curb. No crashes or injuries are recorded in this category.

Rattles from behind the glove box and the head-up display start as early as 2,000 miles. Some cars make a loud, high-pitched reedy noise at highway speed in strong wind. It drowns out music and calls, and Mazda has not addressed it. In one report, a sunroof shattered outward at highway speed with nothing hitting it, throwing glass at the people inside and toward traffic behind. The interior noises are an annoyance. The sunroof failure is an injury risk.