Typical Clutch Pedal Position (CPP) Switch
The CPP switch is an input to the PCM indicating the clutch pedal position. The PCM provides a low current voltage on the CPP circuit. When the CPP switch is closed, this voltage is pulled low through the signal return (SIGRTN) circuit. The CPP input to the PCM is used to detect a reduction in engine load. The PCM uses the load information for mass airflow and fuel calculations.