Throttle Position Sensor: Testing and Inspection

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 Prerequisites

• Fuses in E-box (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.

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

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

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

• Ignition is switched off.

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

Test Sequence

- Remove footwell cover (driver's side).

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

- Switch ignition on.

Checking Voltage Supply and Wiring

- 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:

- Connect test box ((VAG1598/42)) to Engine Control Module (ECM) (J623) wiring harness using adapter cable ((1598/39-2)) , connecting test box for wiring test.

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





Terminal 1 + socket 59

Terminal 2 + socket 84

Terminal 3 + socket 39

Terminal 4 + socket 83

Terminal 5 + socket 61

Terminal 6 + socket 17

Wire resistance: max. 1.5ohms

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

Specified value: infinite ohms

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

- Replace Throttle Position (TP) Sensor (G79).

- Erase DTC memory of Engine Control Module (ECM) --> [ Diagnostic Mode 04 - Erase DTC Memory ] .

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