Clutch Position Sensor Circuit Low
Diagnostic trouble code P0807 indicates that the Powertrain Control Module (PCM) or Transmission Control Module (TCM) has detected a low voltage signal from the clutch position sensor circuit. This typically means the signal voltage fell below the manufacturer's specified minimum threshold, suggesting a short to ground or a faulty sensor.
While not immediately dangerous, this code can prevent the vehicle from starting (due to the starter interlock) or cause drivability issues. It should be diagnosed and repaired soon to avoid being stranded.
Common symptoms
- Illuminated Check Engine Light
- Engine will not crank or start
- Harsh or erratic shifting (in automated manual transmissions)
- Cruise control inoperative
- Engine stalling when coming to a stop
Likely causes
- Faulty clutch position sensor
- Wiring harness shorted to ground in the sensor circuit
- Corroded, damaged, or loose electrical connector
- Improperly adjusted clutch position sensor
- Mechanical issue with the clutch pedal assembly
- Faulty PCM or TCM (rare)
What to check before replacing parts
Visually inspect the clutch position sensor, wiring, and connectors.
Look for: Look for frayed wires, melted insulation, corrosion in the connector pins, or physical damage to the sensor itself.
Check the sensor's mechanical adjustment and mounting.
Look for: Ensure the sensor is securely mounted and properly aligned with the clutch pedal movement, and that the pedal itself is not loose or damaged.
Test the reference voltage and ground at the sensor connector using a digital multimeter.
Look for: With the key on, engine off, verify the presence of a 5-volt reference signal and a solid ground. A missing reference voltage indicates a wiring or module issue.
Test the sensor signal output voltage while operating the clutch pedal.
Look for: The voltage should smoothly transition (typically between 0.5V and 4.5V) as the pedal is pressed and released. A constant low voltage (near 0V) indicates a short to ground or a dead sensor.
Check for continuity and shorts to ground in the signal wire between the sensor and the PCM/TCM.
Look for: Disconnect both ends of the harness and test the signal wire. Resistance to ground should be infinite (OL); if there is continuity to ground, the wire is shorted.
This page explains the generic P0807 definition and is general reference information, not a diagnosis for your specific vehicle. Actual causes, severity, and repairs vary by make, model, engine, and mileage — always confirm with a scan tool and a qualified technician before replacing parts.
Gear guide: Best OBD2 ScannersRead this code yourself next time — from $20 Bluetooth dongles to bidirectional scan tools.Rather have a pro handle it? Find a vetted local mechanic.