2025 Tesla Model Y: What to check before buying

The AP4 driver-assist computer fails on nearly new cars, often within the first 1,000 miles. When it fails, it takes out all cameras including the backup camera, plus GPS, navigation, cruise control, automatic emergency braking, blind spot and lane warnings, and automatic wipers. Several reports describe service dates weeks away, parts on back order, and no loaner. Other complaints cover a horn that goes quiet in rain, a touchscreen that goes black until a hard reboot, and Autopilot driving through a red light. Two reports involve fire, one of them a fatal crash.

Phantom braking leads these complaints. With Traffic Aware Cruise Control or Autopilot on, the car brakes hard for vehicles in the next lane, curve signs, or turning traffic at a safe distance. A Curvature Assist message also appears on straight roads and cuts speed sharply. Owners fear being rear-ended. In Full Self-Driving reports, the car swerves toward oncoming traffic or nearby vehicles and steers toward a road marked Do Not Enter. Early AP4 computer failures also show up here, disabling the backup camera and collision warnings. One crash involves unintended acceleration while parking.

Hard braking with nothing ahead is the most common complaint. It happens with cruise control or Autopilot on, and one driver reports whiplash. Owners also say automatic emergency braking turns itself back on every time they disable it. The opposite failure appears too. The car keeps moving despite firm pedal pressure, or rolls forward while parked on a nearly flat, snowy driveway, and both cases end in collisions. Other reports describe regenerative braking, traction control, stability control, and vehicle hold dropping out at random. The removal of creep mode forces drivers to maneuver at low speed on the accelerator.

Full Self-Driving errors cause most crashes here. The system shuts off suddenly in the middle of a turn and the car crosses lanes at highway speed, or it fails to finish a lane change and clips a truck in the next lane without warning. The car also misses a parked car directly behind while backing up and gives no alert. The other reports describe the AP4 computer failure, which disables cameras, navigation, and collision and lane features and leaves the mirrors stuck dark. Repair dates keep slipping and no loaner is offered.

Unintended acceleration causes the serious crashes. The car lunges forward while the brake is pressed, or surges out of control when shifted into Reverse or Drive, hitting trees and objects in the garage. One crash left a driver injured after the car left the road and rolled down a hill. Pressing the right stalk by mistake can also make the car speed up. A Full Self-Driving update removed driver-set speed targets, and the system misreads speed limits by as much as 25 mph, which causes sudden speed changes. Early AP4 computer failure also appears.

Every report here describes losing steering control. Under Full Self-Driving or Autopilot, the car leaves its lane on its own, darting into a guardrail or driving head-on into a tree. Steering that locks in the rain, with brakes that do not respond, is also reported. A Steering Assist Reduced alert, error code GTW_w075, makes the steering extremely heavy within weeks of delivery. The car becomes unsafe to drive and has to be towed. Three of the four complaints involve crashes, one with an injury.

Airbags fail to deploy in serious crashes. The reports include a T-bone collision that totaled the car, a high-speed impact on the passenger side, and a front-end crash into a tree at about 30 mph. In two of these crashes, the seat belts also fail to lock or retract. Two of the three reports involve injuries. One failure happened at 4,444 miles, and that car was still waiting for diagnosis at a Tesla Service Center. No cause or repair is reported.

The windshield cracks when defrost runs in extreme cold. One case happened in single-digit temperatures on a car with 14,000 miles that was less than a year old, and Tesla refused to cover the replacement. The other report repeats the AP4 computer failure seen across this model year. After a software update, the cameras, cruise control, collision and lane warnings, blind spot warning, and GPS navigation all stop working.