P0122

P0122
Throttle Position (TP)Sensor Entry Signal Too Low

P0123
Throttle Position (TP) Sensor - Entry Signal Too High

Function
The TP Sensor determines the position of the throttle valve. The TP Sensor is supplied with + 5 Volt through pin 53 of the Engine Control Module (ECM) and through pin 34 connected to ground. The TP Sensor signal voltage is between approximately 0.5 Volt to approximately 4.7 Volt, depending on the position of the throttle valve. The idle contact is generated from the voltage value that occurs during the load phase.
The value for the wide open throttle contact is calculated from the value of the generated idle contact.

Diagnostic conditions

P0122
A fault is recognized and stored in the memory if the voltage is below 0.15 Volt and the engine speed is above 400 1/min.

P0123
A fault is recognized and stored in the memory if the voltage is above 4.85 Volt and if the engine speed is above 400 1/min.





Wiring Diagram





Diagnostic procedure

Check voltage supply to TP Sensor.
1. Connect adapter cable V.A.G. 1501 between disconnection of TP Sensor.
2. Switch on ignition.
3. Connect voltmeter to wire No. 1 (plus) and No. 2 (minus).

- Specified value: approx. 5 V

4. Connect voltmeter to wire No.1 (plus) and No. 3 (minus)

- Specified value at closed throttle valve: approx. 4.5 V.

5. Depress accelerator pedal all the way. Throttle valve must be wide open.

- Specified value: approx. 0.5 V

Check TP Sensor.
1. Remove connector for TP Sensor.
2. Connect ohmmeter to TP Sensor, pin 1 and pin 2.

- Specified value: 1.6 - 2.4 kohms

3. Connect ohmmeter to 2 and pin 3

- Specified value: 710 - 1380 ohms

Check wiring From disconnection between TP Sensor and ECM for continuity or short circuit to 6+ or ground.
1. Separate disconnection point to TP sensor.
2. Remove ECM.
3. Connect ohmmeter between disconnection point pin 1 and ECM connector pin 53. Display: 0 - 5 ohms
4. Connect ohmmeter between disconnection point pin 2 and ECM connector pin 34. Display: 0 - 5 ohms
5. Connect ohmmeter between disconnection point pin 3 and ECM connector pin 44. Display: 0 - 5 ohms.
6. Fit ECM connector and switch on ignition.
7. Connect voltmeter to pin 1 and ground. Display: approx. 5 Volt
8. Connect voltmeter to pin 2 and ground. Display: 0 Volt
9. Connect voltmeter to pin 3 and ground. Display: 0 Volt
10. Connect voltmeter to disconnection point pin 1 and positive. Display: approx. 0 Volt
11. Connect voltmeter to disconnection point pin 3 an positive. Display: approx. 6 Volt

- Check wiring harness for trapped locations and abrasions if battery voltage is displayed for Points 7 through 11.