Manufacture of a speed sensor, including a cable (15) containing electrical wires for connection between the sensor and a data processing unit, pins joined to the wires and to connection blades of a member for detecting the rotation speed of the wheel of the vehicle, a first molded plastic casing portion (3), having a shaft (13) molded around one end of the wires of the cable, and a cavity in which the pins and the detection member are placed, the pins being mutually separated and the wires being mutually separated at the point of their stripped end, and the detection member being held in place in the cavity of the first casing portion by retaining lugs made of one piece with this first casing portion, and a second casing portion (5) including a part that isolates the pins and the detection member from the outside.