The P0843 code in your 2020 Toyota Tundra indicates the clutch actuator position sensor A circuit is providing a higher voltage signal than expected. This internal transmission sensor reading issue affects clutch engagement monitoring and control.
Understanding High Input Faults
A high input reading from sensor A indicates elevated voltage in the circuit. This typically occurs from open grounds, shorts to power, or sensor failures that cause the output to rail high.
Common Causes of P0843
- Open circuit in sensor ground
- Short to battery voltage
- Sensor internal failure
- Disconnected or damaged wiring
- Connector issues causing open ground
- TCM input circuit problem
Symptoms of High Input
- Incorrect clutch position indicated
- Check engine light on
- Transmission shift issues
- Possible engagement problems
- TCM protection modes active
- Rough shifting
Tundra Transmission Design
The Tundra's 6-speed automatic is designed for truck duty including towing. Accurate clutch position sensing is important for proper engagement under various load conditions.