Throttle/Pedal Position Sensor/Switch B Circuit Range/Performance
Common Symptoms
- Check Engine Light illuminated
- Reduced engine power or limp mode activated
- Poor throttle response or hesitation during acceleration
- Engine surging or unstable idle
- Vehicle may enter fail-safe mode with limited speed
- Inconsistent or erratic acceleration
Most Likely Root Causes
- Faulty throttle position sensor or accelerator pedal position sensor
- Damaged or corroded wiring harness or connectors at sensor
- Throttle body contamination or carbon buildup affecting sensor operation
- Failed or sticking throttle body actuator
- Poor electrical ground connection at sensor or PCM
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Component Location
The throttle position sensor is typically integrated into the throttle body assembly, while the accelerator pedal position sensor is located at the top of the accelerator pedal mechanism.
Manufacturer Notes
Many drive-by-wire systems require sensor correlation relearn procedures after throttle body cleaning or component replacement.
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