General Information

P0123 Throttle Position Sensor 1 Signal Circuit High Input

General Information

Component Location





General Description

The Throttle Position Sensor (TPS) is mounted on the throttle body and detects the opening angle of the throttle plate. The TPS has a variable resistor (potentiometer) whose characteristic is the resistance changing according to the throttle angle. During acceleration, the TPS resistance between the reference 5 V and the signal terminal decreases and output voltage increases; during deceleration, the TPS resistance increases and TPS output voltage decreases. The PCM supplies a reference 5 V to the TPS and the output voltage increases directly with the opening of the throttle valve. The PCM determines operating conditions such as idle (closed throttle), part load, acceleration/deceleration, and wide-open throttle from the TPS. Also The PCM uses the Mass Air Flow Sensor (MAFS) signal along with the TPS signal to adjust fuel injection duration and ignition timing.

DTC Description

PCM sets DTC P0123 if the PCM detects signal voltage higher than the possible range of a properly operating TPS.

DTC Detecting Condition





Specification





Diagnostic Circuit Diagram





Signal Waveform & Data
















Fig.1) Signal increases proportionally with throttle open and close angle
Fig.2) Normal value with IG "ON"
Fig.3) Open in signal or ground circuit : Approx. 5 V