Operation CHARM: Car repair manuals for everyone.

Circuit Description

With the ignition switch in ON (II) or START (III), battery voltage is supplied from fuse 24 through the BLK/YEL wire to the Vehicle Speed Sensor (VSS). The sensor is grounded by the BLK wire to G101. The speedometer and other control units in the circuit supply about 5 volts to the ORN wire. The vehicle speed sensor (VSS) intermittently grounds the ORN wire which generates a pulsed signal in it. The number of pulses per minuteincreases/decreases with the speed of the car.