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 ECM 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
ECM sets DTC P0122 if the ECM detects signal voltage lower than the possible range of a properly operating TPS.
Item
Detecting Condition
Possible cause
DTC Strategy
? Signal check, low
? Short to ground in signal circuit (pin 16 to 17)
? Open in power circuit (pin 32)
? Faulty TPS
? Faulty ECM
Threshold value
? Calculated signal from sensor : < 3.17%
Enable Conditions
Diagnostic Time
? 0.02 sec
Fail Safe
? Throttle position value is determined by function of engine speed, MAP sensor and idle duty.
TPS
Normal Parameter
Idle position
WOT
Throttle angle
5 ~ 16°
80 ~ 98°
Signal Voltage
0.25 ~ 0.8 V
4.0 ~ 4.8 V
Resistance(terminal 1 and 2)
0.71 ~ 1.38 ?
2.2 ~ 3.4 ?
Resistance(terminal 2 and 3)
1.6 ~ 2.4 ? at all throttle position
Hi-scan Data display
0%
75 ~ 85 %
When checking TPS waveform,it is strongly recommended to examine waveform with MAP sensor waveform.
Periode ? Is the voltage of MAP in idling and 0.8~1.2 V,and there must be a little fluctuation in waveform.
In case there is no fluctuation
Possible cause : Deteriorated MAP sensor or some foreign material in TPS sensor.
The voltage in Periode ? Is 0.3~1.0V in average.
Periode ? Is in W.O.T and the voltage there is 4.3 V, and MAP sensor voltage is about 4.3 V.