Throttle Position Sensor: Testing and Inspection

Throttle Position (TP) Sensor, Checking
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.

Recommended special tools and equipment
- V.A.G1526 multimeter or V.A.G1715 multimeter
- V.A.G1594 connector test kit
- Wiring diagram

Test requirement
- The respective fuses of Engine Control Module (ECM) must be OK

Test sequence

NOTE: 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.

Checking voltage supply and wiring to control module
- Switch ignition on.







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

Connector at wiring Specified value
harness, terminal
1 + Ground (GND) approx. 5 Volts
1 + 5 approx. 5 Volts
2 + Ground (GND) approx. 5 Volts
2 + 3 approx. 5 Volts

- Switch ignition off.

If the specified values are not reached, check wire connections.

Checking wire connections







- Connect V.A.G 1598/31 test box to wiring harness of Engine Control Module (ECM) Scan Tool Connecting
- Check the following wire connection for open circuit/short circuit.

Connector at wiring V.A.G 1598/31 test box or
harness,terminal Engine Control Module (ECM)
1 72
2 73
3 36
4 35
5 33
6 34

- 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: Infinity 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 4 Reset/erase diagnostic data.
- Generate readiness code.