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E024

Code E24:




VSS Circuit:






DESCRIPTION:

The PCM/ECM receives unbuffered speed information from the vehicle speed sensor located in the transaxle assembly. If the PCM/ECM detects 0 MPH when the engine RPM and TPS indicate that the vehicle is moving, code E24 is set. To avoid any erratic cruise control operation due to an intermittent problem, the cruise control system is disabled for the entire ignition cycle.

TEST CONDITIONS:

1. Codes E21, E22, E26, and E27 are not set.
2. Transmission in drive or reverse.
3. Brake off.
4. Throttle switch open.
5. Throttle angle 17° or greater.
6. Engine speed greater than or equal to 1400 RPM.

FAILURE CONDITIONS:

Vehicle Speed = 0 MPH for 3 seconds.

ACTION TAKEN:

1. PCM/ECM illuminates "SERVICE ENGINE SOON" telltale.
2. Disable VCC and cruise for the entire key cycle.

NOTES ON FAULT TREE:

1. The vehicle speed sensor provides a 0 to 36 volt AC signal to the PCM/ECM depending on vehicle speed. With the tires moving, the signal to the PCM/ECM should be greater than 0.5 volts AC.

NOTE ON INTERMITTENTS:

If code E24 is a history code, select parameter P.0.9, lift drive wheels, place transmission in drive, and allow wheels to turn. Manipulate affected wiring while observing parameter P.0.9. If fault is induced, parameter P.0.9 will momentarily drop to 0 MPH. Check for intermittent opens or shorts to ground on CKT 400 and 401. Check terminal contact at the speed sensor and that the PCM/ECM connector.