Throttle Position Sensor, Checking

Diagnostic Procedures

Throttle Position Sensor, Checking

Special tools, testers and auxiliary items required

• Multimeter (VAG1526) or multimeter (VAG1715)

• Connector test kit (VAG1594)

• Wiring diagram

Test requirements

• Fuses in E-box (in plenum chamber, left) must be OK:





• Battery voltage must be at least 11.5 volts.

• All electrical consumers such as, for example, lights and rear window defroster must be switched off.

• Parking brake must be engaged or else daylight driving lights will be switched on.

• For vehicles with automatic transmission, selector lever must be in P position.

• If vehicle is equipped with an A/C system, it must be switched off.

• Ground (GND) connections between engine and chassis must be OK.

Function

Both the Throttle Position (TP) Sensor (G79) and the Sender -2- for accelerator pedal position (G185) are located at the accelerator pedal and communicate the driver's intentions to the ECM completely independently of each other. Both sensors are stored in one housing.

Test sequence

• When servicing terminals in the harness connector for the Throttle Position (TP) Sensors, use only gold-plated terminals.

- Remove footwell cover (driver's side).

- Disconnect 6-pin connector from Throttle Position (TP) Sensor.

- Switch ignition on.

Checking voltage supply

- Connect multimeter to the following connector terminals for voltage measurement.





Terminal 1 + Ground (GND)

Terminal 1 + 5

Terminal 2 + Ground (GND)

Terminal 2 +3

Specified value: at least 4.5 V

- Switch ignition off.

If specified values are not obtained:

- Check wires according to wiring diagram.

Checking wiring

- Connect test box to control module wiring harness , connect test box for wiring test.

- Check wires between test box and 6-pin connector for open circuit according to wiring diagram.





Terminal 1+socket 72

Terminal 2+socket 73

Terminal 3 + socket 36

Terminal 4 + socket 35

Terminal 5 + socket 33

Terminal 6 + socket 34

Wire resistance: max. 1.5 ohms

- Also check wires for short circuit to each other, to vehicle Ground (GND) and to B+.

Specified value: infinite ohms

- Erase DTC memory of Engine Control Module (ECM) , Diagnostic mode 4: Reset/erase diagnostic data.

- Generate readiness code.

If no malfunction is detected in the wiring and if the voltage supply was OK:

- Replace Throttle Position (TP) sensor.

- Erase DTC memory of Engine Control Module (ECM) , Diagnostic mode 4: Reset/erase diagnostic data.

- Generate readiness code.