Clutch Switch: Description and Operation

Typical Clutch Pedal Position (CPP)/Park-Neutral Position (PNP) Switches:

PURPOSE
The Clutch Pedal Position (CPP) switch is an input to the Powertrain Control Module (PCM) indicating clutch pedal position and in some applications both the clutch engagement and gear shift position. The PCM adjusts the idle speed and air/fuel ratio according to input from the CPP switch.

OPERATION
A 5.0 volt reference signal is applied to the CPP from the PCM. If the CPP switch is closed, indicating the clutch pedal is engaged and the shift lever is in the neutral position, the output voltage from the PCM is grounded through the Signal Return line to the PCM and there is 1 volt or less. One volt indicates a reduced load on the engine. If the CPP switch is open (clutch pedal disengaged, shift lever not in neutral) the input on the CPP signal will be approximately 5 volts, indicating a load on the engine.