Throttle/Pedal Position Sensor/Switch B Circuit Intermittent
Common Symptoms
- Check Engine Light illuminated
- Intermittent loss of throttle response or hesitation during acceleration
- Engine may enter limp mode with reduced power
- Erratic or surging idle speed
- Throttle response feels inconsistent or delayed
Most Likely Root Causes
- Intermittent wiring or connector issues at throttle position sensor or accelerator pedal sensor
- Corroded or loose connector pins at sensor B circuit
- Failing throttle position sensor or accelerator pedal position sensor
- Damaged wiring harness with intermittent short or open circuit
- Poor ground connection at sensor or control module
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Component Location
Throttle position sensor is mounted on the throttle body; accelerator pedal position sensor is integrated into the accelerator pedal assembly.
Manufacturer Notes
Some manufacturers use dual throttle position sensors or dual accelerator pedal sensors for redundancy and fault detection purposes.
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