Circuit Description

Vehicle speed sensor outputs a 4-pulse input signal for every revolution of the drive gear in transmission to the instrument cluster where input signal is converted to a rectangular waveform and then sent to ECM. ECM determines vehicle speed by using input signal. DTC is set if there is no vehicle speed signal to ECM while vehicle is being driven and park/neutral position switch is off. Possible causes are:

• Defective vehicle speed sensor.
• Vehicle speed sensor circuit is open or shorted.
• Defective instrument cluster.
• Defective ECM.