Throttle/Pedal Position Sensor/Switch B Circuit Malfunction
Common Symptoms
- Check Engine Light illuminated
- Reduced engine power or limp mode activated
- Poor throttle response or delayed acceleration
- Engine idle fluctuates or surges
- Vehicle may not accelerate beyond a certain speed
- Cruise control inoperative
Most Likely Root Causes
- Faulty accelerator pedal position sensor
- Damaged or corroded wiring harness to throttle position sensor
- Poor electrical connection at sensor connector
- Failed throttle body position sensor
- ECM internal fault
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Component Location
Accelerator pedal position sensor is located at the top of the accelerator pedal assembly; throttle position sensor is mounted on the throttle body.
Manufacturer Notes
Some manufacturers use redundant accelerator pedal position sensors with separate circuits for safety verification and fault detection.
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