Lane Assist provides steering interventions if Model S drifts into (or close to) an adjacent lane in which an object, such as a vehicle, is detected. In these situations, Model S automatically steers to a safer position in the driving lane. This steering is applied only when Model S is traveling between 30 and 85 mph (48 and 140 km/h) on major roads with clearly visible lane markings. When a steering intervention is applied, the instrument panel briefly displays a warning message.

Lane Departure Avoidance is designed to warn you if Model S is drifting out of, or nears the edge of, your driving lane.

Lane Departure Avoidance operates when driving between 40 and 90 mph (64 and 145 km/h) on roads with clearly visible lane markings. You can choose if and how you want Lane Departure Warning to operate by touching Controls > Autopilot > Lane Departure Avoidance and selecting between these options:

• Off: You are not warned of lane departures or potential collisions with a vehicle in an adjacent lane.
• Warning: If a front wheel passes over a lane marking, the steering wheel vibrates. (For vehicles equipped with Full Self-Driving (Supervised): if a front wheel passes over a lane marking, the steering wheel vibrates.)
• Assist: Corrective steering is applied to keep Model S in a safe position if Model S drifts into an adjacent lane or near the edge of the road.

When Lane Departure Avoidance is enabled and Traffic-Aware Cruise Control is active, if Model S drifts out of the driving lane when the associated turn signal is off, Lane Assist also checks to see whether your hands are on the steering wheel. If hands are not detected, the instrument panel displays a series of alerts, similar to those that are used when driving with Autosteer. If hands are repeatedly not detected Model S gradually slows down to 15 mph (25 km/h) below the detected speed limit, or below the set cruising speed, and the hazard lights start flashing.

Emergency Lane Departure Avoidance automatically applies steering to avoid a potential collision in situations where:

• Model S is departing a lane and may collide with a vehicle traveling in the same direction in the adjacent lane (regardless of the status of the turn signal).
• Model S is departing a lane into an oncoming lane, the turn signal is off, and an oncoming vehicle is detected.
• Model S is departing the road and the turn signal is off (for example, very close to the edge of the road and a collision may occur).

To turn this feature on or off, touch Controls > Autopilot > Emergency Lane Departure Avoidance.

When Emergency Lane Departure Avoidance applies steering, a chime sounds and the instrument panel displays a warning and highlights the lane marking in red.

Emergency Lane Departure Avoidance operates when Model S is traveling between 40 and 90 mph (64 and 145 km/h) on a road with clearly visible lane markings, curbs, etc.

Lane Assist features cannot always detect lane markings and you may experience unnecessary or invalid warnings when:

• Visibility is poor and lane markings are not clearly visible (due to heavy rain, snow, fog, etc.).
• Bright light (such as from oncoming headlights or direct sunlight) is interfering with the view of the camera(s).
• A vehicle in front of Model S is blocking the view of the camera(s).
• The windshield is obstructing the view of the camera(s) (fogged over, dirty, covered by a sticker, etc.).
• Lane markings are excessively worn, have visible previous markings, have been adjusted due to road construction, or are changing quickly (for example, lanes branching off, crossing over, or merging).
• The road is narrow or winding.
• Objects or landscape features are casting strong shadows on lane markers.

Lane Assist may not provide warnings, or may apply inappropriate warnings, when:

• One or more of the sensors (if equipped), or cameras is damaged, dirty, or obstructed (by mud, ice, or snow, or by a vehicle bra, excessive paint, or adhesive products such as wraps, stickers, rubber coatings, etc.).
• Weather conditions (heavy rain, snow, fog, or extremely hot or cold temperatures) are interfering with sensor operation.
• The sensors (if equipped) are affected by other electrical equipment or devices that generate ultrasonic waves.
• An object that is mounted to Model S is interfering with and/or obstructing a sensor (such as a bike rack or a bumper sticker).

In addition, Lane Assist may not steer Model S away from an adjacent vehicle, or may apply unnecessary or inappropriate steering, in these situations:

• You are driving Model S on sharp corners or on a curve at a relatively high speed.
• Bright light (such as from oncoming headlights or direct sunlight) is interfering with the view of the camera(s).
• You are drifting into another lane but an object (such as a vehicle) is not present.
• A vehicle in another lane cuts in front of you or drifts into your driving lane.
• Model S is not traveling within the speeds at which the Lane Assist feature is designed to operate.
• One or more of the sensors (if equipped) is damaged, dirty, or obstructed (such as by mud, ice, or snow, or by a vehicle bra, excessive paint, or adhesive products such as wraps, stickers, rubber coating, etc.).
• Weather conditions (heavy rain, snow, fog, or extremely hot or cold temperatures) are interfering with sensor operation.
• The sensors (if equipped) are affected by other electrical equipment or devices that generate ultrasonic waves.
• An object mounted to Model S (such as a bike rack or a bumper sticker) is interfering with or obstructing a sensor.
• Visibility is poor and lane markings are not clearly visible (due to heavy rain, snow, fog, etc.).
• Lane markings are excessively worn, have visible previous markings, have been adjusted due to road construction or are changing quickly (for example, lanes branching off, crossing over, or merging).