Throttle Position Sensor: Testing and Inspection

Throttle Position Sensor, Checking

Both the Throttle Position (TP) Sensor (G79) and Accelerator Pedal Position Sensor 2 (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.

Special tools, testers and auxiliary items required

• Multimeter (VAG1526) or Multimeter (VAG1715)

• Connector test kit (VAG1594)

• Wiring diagram

Test Prerequisite

• The respective fuses of Engine Control Module (ECM) must be OK:

Test Sequence

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

- Remove footwell cover (driver's side).

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

Voltage Supply, Checking

- Switch ignition on.

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









- Switch ignition off.

If specified values are not reached, check wire connections.

Wiring, Checking

- Connect test box (VAG1598/31) to wiring harness of Engine Control Module (ECM),





- Check the following wire connection for open circuit/short circuit:





- Repair open circuit in wiring or short circuit if necessary.

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

Specified value: infinite ohms (no continuity)

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

- Replace accelerator pedal module,

- Erase DTC memory of Engine Control Module (ECM) => [ Diagnostic Mode 04 - Erase DTC Memory ] Diagnostic Modes 01 - 09, Diagnostic mode 4: Reset/erase diagnostic data.

- Generate readiness code => [ Readiness Code, Generating ] Monitors, Trips, Drive Cycles and Readiness Codes.