BCM DTC B124: Vehicle Speed Sensor (VSS) Circuit Problem: Description

The vehicle speed sensor uses a permanent magnet P.M. generator to produce an electrical signal representative of vehicle speed. This signal is sent to the ECM by CKTs 400 (VSS HI) and 401 (VSS LO) where the ECM buffers and amplifies the signal for its prospective uses. Output of the generator can be seen by using a digital voltmeter on the AC scale while rotating the generator drive (rotate front wheels).