P0805

Symptoms

• Check engine light
• sometimes with a transmission warning lamp
• engine may not crank even with the clutch pedal fully depressed
• or intermittent no-crank when turning the key
• engine may start without the clutch pedal depressed
• in rare cases no symptoms at all. Safety note: on vehicles with remote start
• the engine could start without the clutch depressed and the vehicle could begin to move.

Probable causes

• 1) Defective clutch position sensor/switch. 2) Damaged
• shorted
• burnt
• disconnected
• or corroded wiring and/or connectors between the sensor and the PCM. 3) Incorrect adjustment or misalignment of the switch. 4) Loose or oxidized electrical connections.

Diagnostic steps

1. Connect a scan tool, confirm P0805 is active, record all fault codes and freeze frame data; resolve any voltage-related codes first.
2. Locate the clutch position sensor/switch and inspect it for damage, overheating, or misalignment; check the connector for looseness, corrosion, or defects.
3. With a multimeter, verify full battery voltage reaches the connector power supply terminal; if voltage is absent, check ground straps and fuses.
4. Manually actuate the switch while monitoring output voltage as the pedal is depressed and released; compare sensor resistance and output voltage against OEM specifications.
5. If supply voltage is present but current does not pass through the switch when activated, replace the switch.
6. If the code persists, suspect intermittent wiring faults and repeat the wiring tests.