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 5V 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 5V to the TPS and the output voltage increases directly with the opening of the throttle valve. The TPS output voltage will vary from 0.2~0.8V at closed throttle to 4.3~4.8V at wide-open throttle.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.
PCM sets DTC P0123 if the PCM detects signal voltage higher than the possible range of a properly operating TPS.
Item | Detecting Condition | Possible Cause |
DTC Strategy | ● Voltage range check | ● Open in signal or ground circuit. ● Short to battery in signal circuit. ● Contact resistance in connectors. ● Faulty TP sensor. |
Enable Conditions | ● 6 ≤ Battery voltage ≤ 16V | |
Threshold value | ● Voltage ＞ 4.86 V | |
Diagonostic Time | ● 1 sec. | |
Fall Safe | ● Throttle position value is determined by function of engine speed, mass air flow and idle duty. |
TPS | Fully Closed | Fully Open | |
Throttle Angle (°) | 0~0.5° | 86° | |
Signal Voltage (V) | 0.2~0.8V | 4.3~4.8V | |
Resistance(kΩ) | Terminal 1 and 2 | 0.71 ~ 1.38kΩ at all temperature | 2.7kΩ at all temperature |
Terminal 2 and 3 | 1.6 ~ 2.4 ㏀ at all throttle position |
