Throttle/Pedal Position Sensor/Switch A Circuit Low Input
Common Symptoms
- Check Engine Light illuminated
- Engine stalls or dies at idle
- Poor acceleration or lack of throttle response
- Engine may start then immediately stall
- Reduced power or limp mode activation
- Idle speed higher or lower than normal
Most Likely Root Causes
- Faulty throttle position sensor
- Damaged or corroded wiring harness to TPS
- Poor electrical connection at TPS connector
- Short to ground in TPS signal circuit
- Failed accelerator pedal position sensor on drive-by-wire systems
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Component Location
Throttle position sensor is mounted on the throttle body assembly, typically on the side of the throttle shaft.
Manufacturer Notes
Many vehicles with electronic throttle control may require throttle body relearn procedure after sensor replacement or reconnection.
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