Vehicle Speed Sensor Check (2WD & AWD): Notes

The Vehicle Speed Sensor (VSS) circuit consists of a magnetic induction-type sensor, vehicle speed sensor buffer module and wiring. Gear teeth, pressed on the outside diameter of output carrier assembly, induce an alternating current in the sensor. This current is transmitted to the buffer module. Buffer module compensates for various axle ratios, and converts signal to a square wave for use by speedometer, cruise control, anti-lock brake system and PCM. 5 Buffer module sends 2 different signals to PCM. Circuit No. 437 relays transmission output speed, which is used to control shift points, line pressure, TCC, Code 24 and Code 72. Circuit No. 1716 relays vehicle speed, which is used to control engine operating functions and Code 16.

1. This test checks the VSS signal to the PCM.
2. This test checks the VSS signal to the buffer module.
3. This test checks the VSS signal.