The PCM has detected an implausible or erratic signal from the clutch pedal position switch circuit, which reports whether the clutch is depressed or released. This input is used for starter interlock logic, cruise control cancellation, and deceleration fuel-cutoff strategies on manual transmission vehicles.
The internal contacts wear, corrode, or carbon-track, preventing consistent continuity when the pedal is pressed or released.
Open circuits, shorts to ground or power, or high resistance in the harness between the switch and PCM due to chafing, moisture intrusion, or pin corrosion.
The switch may be loose on its bracket or the pedal stop may be worn, preventing full plunger travel and causing intermittent contact.
Poorly integrated remote start systems or alarms that interrupt the clutch circuit can introduce resistance or voltage spikes that confuse the PCM.
Rarely, the internal pull-up or sensing circuit within the PCM fails to recognize a valid switch signal despite correct voltage at the connector.
Generally yes, though you may experience intermittent no-start conditions if the starter interlock is affected, or cruise control may not function properly.
No. The physical switch, wiring, or adjustment is the cause in the vast majority of cases. PCM failure is extremely rare for this circuit and should only be considered after all other possibilities are eliminated.
The PCM uses the clutch switch input to immediately disengage cruise control when the pedal is pressed; a fault in this circuit may prevent cruise engagement or cause it to ignore the clutch input.
No. P0704 is specific to manual transmission vehicles equipped with a clutch pedal position switch.