Sec. 642.

(1) When a roadway has been divided into 2 or more clearly marked lanes for traffic the following rules in addition to all others consistent with this act shall apply:

(a) A vehicle shall be driven as nearly as practicable entirely within a single lane and shall not be moved from the lane until the driver has first ascertained that the movement can be made with safety. Upon a roadway with 4 or more lanes which provides for 2-way movement of traffic, a vehicle shall be driven within the extreme right-hand lane except when overtaking and passing, but shall not cross the center line of the roadway except where making a left turn.

(b) Upon a roadway which is divided into 3 lanes and provides for 2-way movement of traffic, a vehicle shall not be driven in the center lane except when overtaking and passing another vehicle traveling in the same direction, when the center lane is clear of traffic within a safe distance, or in preparation for a left turn, or where the center lane is at the time allocated exclusively to traffic moving in the same direction the vehicle is proceeding and the allocation is designated by official traffic control devices.

(c) Official traffic control devices may be erected directing specified traffic to use a designated lane or designating those lanes to be used by traffic moving in a particular direction regardless of the center of the roadway and drivers of vehicles shall obey the directions of the traffic-control device.

(d) Official traffic-control devices may be installed prohibiting the changing of lanes on sections of roadway, and drivers of vehicles shall obey the directions of the traffic-control devices.

(2) When any lane has been designated as an HOV lane under section 1 of 1951 PA 51, MCL 247.651, and has been appropriately marked with signs and pavement markings, the lane shall be reserved during the periods indicated for the exclusive use of buses and HOVs. The restrictions imposed on HOV lanes do not apply to any of the following:

(a) Authorized emergency vehicles.

(b) Law enforcement vehicles.

(c) Motorcycles.

(d) Transit and commuter buses designed to transport persons, including the driver.

(e) Vehicles of public utility companies that are responding to an emergency call.

(f) Vehicles that are using an HOV lane to make a turn permitted by law for a reasonable distance in advance of the turn or for purposes of entering or exiting a limited access highway.

(g) Taxicabs having 2 or more occupants, including the driver.

(h) Bicycles, if the HOV lane is the right-hand lane of a highway open to bicycles.

(3) A person who violates this section is responsible for a civil infraction.