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

(Some people have issue connecting. LEMON is investigating. For now, use Firefox or change your DNS server)

Or, hide this message: temporarily or permanently

Vehicle Speed Sensor: Description and Operation

Vehicle Speed Sensor:

Vehicle Speed Sensor (VSS):

PURPOSE
Provides vehicle speed information to the Electronic Control Module (ECM).

OPERATION
The vehicle speed sensor, located in the speedometer drive gear, is a magnetic reed switch that rotates in conjunction with the transmission output shaft. It sends the ECM on/off signals. The ECM interprets the speed at which the on/off signals occur into vehicle speed.