Vehicle Speed Sensor

Vehicle Speed Sensor (VSS) is a magnetic pick-up that sends vehicle speed signal to TCM. Malfunction of sensor may cause harsh engagements of shifts. Lack of 4th gear, TCC lock-up, or engine braking in 2nd or 3rd gear may also be present.

Fig 1: Identifying 4F20E Valve Body Solenoids

Courtesy of FORD MOTOR CO.