ECM Code EO24: Speed Sensor Circuit Problem: Action:
WARNING: This page is about a different car, the 1990 Cadillac Seville and 1990 Cadillac Eldorado. However, it is still accessible from the selected car via links, so may be relevant.
ECM turns on SERVICE ENGINE SOON light and disables Viscous Converter Clutch (VCC) and cruise control. The Vehicle Speed Sensor (VSS) is a permanent magnet pulse generator mounted in the transaxle. The ECM uses VSS input for VCC apply-and release determinations, to select between RPM and throttle angle control of ISC, and as a test condition for many codes.
NOTE:
Test numbers refer to test numbers on diagnostic chart.
Test Number 1) Speed sensor provides a voltage signal to ECM depending upon vehicle speed. With tires moving, signal to ECM should be at least .5 volt AC.