TPS

📖 YOUCANIC Automotive Glossary

The TPS (Throttle Position Sensor) is mounted on the throttle body and reports the exact angle of the throttle plate to the ECU, providing critical data for fuel injection calculation, ignition timing, transmission shift strategy, and cruise control operation. Most modern TPS use dual redundant potentiometers or Hall-effect sensors for safety — the ECU compares both signals and sets a DTC if they disagree. TPS output typically ranges from ~0.5V at closed throttle to ~4.5V at wide-open throttle.

TPS problems cause hesitation, surging, erratic idle, poor acceleration response, and incorrect shift points. DTCs: P0120-P0124 (TPS circuit codes), P2135 (Throttle/Pedal Position Correlation). Many modern vehicles have integrated TPS within the throttle body assembly — the sensor is not separately replaceable. DIYers can monitor TPS voltage in live data and command a smooth sweep from closed to WOT, watching for any dead spots, dropouts, or erratic jumps in the voltage signal.