The Electronic Throttle Control(ETC) system is made of the components throttle body, Throttle Position Sensor(TPS)1&2 and Accelerator Position Sensor(APS) 1&2. TPS1&2 are sharing the same source voltage and ground. The throttle valve opening is control by throttle motor which is controlled by Engine Control Module(ECM). The opposite position indicator shows inverted signal characteristics. TPS1 output voltage increases smoothly in proportion with the throttle valve opening angle after starting. TPS2 output voltage decreases in inverse proportion with the throttle valve opening angle after starting. TPS provides feedback to the ECM to control the throttle motor in order to control the throttle valve opening angle properly in response to the driving condition.
Checking output signals from TPS1 every 8.5 sec. under detecting condition, if an output signal is above 4.75V for more than 0.1 sec., ECM sets P0123. MIL(Malfunction Indication Lamp) turns on when the malfunction lasts till consecutive 2 driving cycle.
Item | Detecting Condition | Possible Cause |
DTC Strategy |
•
Signal high | 1. Poor connection 2. Open or short to battery in signal harness 3. Open in ground harness 4. TPS 5. ECM |
Enable Conditions |
•
IG "ON" | |
Threshold value |
•
The voltage of TPS > 4.75V | |
Diagnosis Time |
•
Continuous (more than 0.1 sec. failure for every 8.5 sec.test) | |
MIL On Condition |
•
1 driving cycles |
Throttle Opening (˚) | Output Voltage (V) [Vref=5.0] | |
TPS1 | TPS2 | |
0˚ | 0.0V | 5.0V |
10˚ | 0.5V | 4.5V |
20˚ | 0.9V | 4.1V |
30˚ | 1.4V | 3.6V |
40˚ | 1.8V | 3.2V |
50˚ | 2.3V | 2.7V |
60˚ | 2.7V | 2.3V |
70˚ | 3.2V | 1.8V |
80˚ | 3.6V | 1.4V |
90˚ | 4.1V | 0.9V |
100˚ | 4.5V | 0.5V |
110˚ | 5.0V | 0.0V |
Fig.1) Normal data of TPS1 & TPS2 with no accel padal depressed under IG ON condition
Fig.2) Normal data of TPS1 & TPS2 with accel padal depressed under IG ON condition
Fig.3) Normal data of TPS1 & TPS2 under open condition
