Code 24, Vehicle Speed Sensor: Notes

WARNING: This page is about a different car, the 1995 Chevrolet Caprice. However, it is still accessible from the selected car via links, so may be relevant.

Speed sensor, which is a Permanent Magnet (PM) generator, provides control module with vehicle speed information. PM generator, mounted in transmission, produces a pulsing AC voltage signal whenever vehicle speed is greater than about 2 MPH. Voltage level and pulses increase with vehicle speed. Control module converts pulsing voltage to MPH, which is used by control module to calculate vehicle adjustments.

NOTE: Test numbers refer to numbers on diagnostic chart.

NOTE: Prior to testing Corvette for Code 24, disable ASR system.

PM generator only produces a voltage signal if drive wheels are turning greater than about 2 MPH.