Operation CHARM: Car repair manuals for everyone.
Manuals through 2025 now available!

Our trusted friends have launched a new website named LEMON, which has newer manuals. It also contains all the CHARM manuals.

LEMON is the spiritual successor to CHARM, I recommend you try it!

Link: lemon-manuals.la or lemon-manuals.org.ua

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Vehicle Speed Sensor: Description and Operation

With the ignition switch in ON (II) or START (III), battery voltage is supplied from fuse 1 through the 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 minute increases/decreases with the speed of the car.