C0100

CIRCUIT DESCRIPTION
The vehicle speed information is provided to the EVO Module by the Vehicle Control Module (VCM) and the class 2 data line. Once vehicle speed has been detected, the EVO Module compares the vehicle speed signal received from the VSS with the vehicle speed data received from the class 2 data line. The VSS is a permanent magnet sensor producing an AC signal with varying frequency. The VSS is mounted in the transmission and is driven off the output shaft. The VSS produces a pulsing AC voltage when vehicle speed is greater than 5 km/h (3 mph). The AC voltage and the number of pulses increase with vehicle speed. The VCM supplies the vehicle speed signal to the Instrument Cluster and to the EVO Module.

CONDITIONS FOR SETTING THE DTC
1. When there is a difference of more than 10 km/h (6 mph) between the class 2 vehicle speed message for 10 seconds and the vehicle speed sensor is less than 5 km/h (3 mph).
2. The above conditions have been met for 5 consecutive class 2 samples.

ACTION TAKEN WHEN THE DTC SETS
The EVO Module will not send any current to the Electronic Variable Orifice (EVO) Solenoid. This will cause the Electronic Variable Orifice (EVO) Solenoid valve to retract providing maximum fluid flow and full power steering assist at all times.

CONDITIONS FOR CLEARING THE DTC
1. A history DTC will clear after 100 consecutive ignition cycles have occurred without a fault.
2. History and current DTC can be cleared by using the Tech 2 scan tool.

DIAGNOSTIC AIDS
- Check for Powertrain code P0500 or any other vehicle speed related codes. If so, perform those diagnostic tables first.
- The scan tool will show vehicle speed when the drive wheels are turning faster than 5 mph. The vehicle speed display should not be used if the drive wheels are not turning.
- An "intermittent" problem may be caused by a poor connection, break in the wire insulation exposing the internal wire, or a wire that is broken inside the insulation.
- The EVO Module and the VCM should be thoroughly checked for terminals that have backed out, broken locks, improperly formed or damaged terminals, weak terminal retaining tension, or for proper routing.





TEST DESCRIPTION
The step numbers below refer to the same step numbers in the Vehicle Speed Information Circuit Malfunction Diagnostic Table.
1. This step ensures that the "Diagnostic System Check" has been performed.
2. This step checks the vehicle speed signal to the VCM.
3. This step makes sure other systems on the same circuit are receiving a VSS signal.