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

PURPOSE
The vehicle speed sensor provides vehicle road speed information to the ECU. The ECU uses this data to properly determine ignition and fuel delivery curves.

LOCATION
The sensor is mounted to the outside of the torque converter case.

OPERATION
The sensor operates whenever the vehicle is moving with ignition ON. As the transmission rotates, the speed sensor sends a pulsed on/off signal to the ECU.