Prizm L4-1800cc 1.8L DOHC (1993)
Vehicle Speed Sensor: Description and Operation
Vehicle Speed Sensor Operation
Function
The Vehicle Speed Sensor (VSS) is an electronic relay that is mounted on the transaxle. As the transaxle turns the VSS, the VSS provides the
speedometer with a vehicle speed input (voltage pulses).
ECM Input
This input is used to drive the speedometer. The speedometer then converts this vehicle speed input into a more precise waveform and provides the
ECM with its own speed input. The ECM converts this this input into a vehicle speed.
Failure Code
A failure in the TPS sensor circuit should set a Diagnostic Trouble Code (DTC) 42.