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Vehicle Speed Sensor: Description and Operation




Vehicle Speed Sensor:





The vehicle speed sensor is mounted inside the speedometer assembly. The sensor consists of a reed switch that is closed by a rotating magnet in the speedometer. The switch shorts ECU pin B11 to ground 4 times every revolution the speedometer cable makes. The sensor is used by the ECU to determine vehicle speed.

The vehicle speed sensor is mounted inside the speedometer assembly. The sensor consists of a reed switch that is closed by a rotating magnet in the speedometer. The switch shorts ECU pin B11 to ground 4 times every revolution the speedometer cable makes. The sensor is used by the ECU to determine vehicle speed.