Throttle Position (TP) Sensor G79 and Accelerator Pedal Position Sensor 2 G185 , checking

Special tools, testers and auxiliary items required 

• Multimeter V.A.G 1526A or Multimeter V.A.G 1526C
• Connector Test Set V.A.G 1594A or Connector Test Set V.A.G 1594C
• Adapter cable, 121-pin V.A.G 1598/31
• Fault Read Out Device V.A.G 1551 or Vehicle Diagnosis, Testing and Information System VAS 5051

• Wiring diagram

Function 

The Throttle Position (TP) Sensor G79 and Accelerator Pedal Position Sensor 2 G185 are located on accelerator pedal and transmit drivers intentions to engine control module completely independent of one another. Both sensors are integrated into one housing.

Test conditions 

• The fuses must be OK.
• Battery voltage must be at least 11.5 Volts.

Test sequence 

• Connect Fault Read Out Device V.A.G 1551 and select engine electronics control module with "Address word 01". For this, the ignition is switched on. Connect fault read out device and select engine control module.

Scan tool display:

Quick data transfer HELP Select function XX

• Press buttons 0 and 8 for function "Reading measuring value blocks" and press Q button to confirm input.

Scan tool display:

Read measuring value block Enter display group number XXX

• Press buttons 0 6 and 2 for "Display group number 62" and press Q button to confirm input.

Scan tool display: (14 = display fields)

Read measured value block 62 -> 1 2 3 4

• Check specified value of Throttle Position (TP) Sensor G79 at idle stop in display field 3.

Specified value: 6 to 96%

• Check specified value of Accelerator Pedal Position Sensor 2 G185 at idle stop in display field 4.

Specified value: 3 to 48%

• Slowly press accelerator pedal to wide open throttle (WOT) position, when doing so, observe percentage display in display fields 3 and 4:

The percentage displays in display field 3 must increase evenly. Specified range 6 to 96% is not completely utilized during this.

The percentage displays in display field 4 must increase evenly. Specified range 3 to 48% is not completely utilized during this.

• Press → key.
• Press buttons 0 and 6 for function "End output" and press Q button to confirm input.
• Switch off ignition.

If readings do not result as described:

• Check voltage supply and sensor wiring connections:

Voltage supply and wiring to control module, checking

• Remove driver-side storage compartment, refer to STORAGE COMPARTMENTS, COVERS AND TRIM .
• Remove 6-pin connector from Throttle Position (TP) Sensor G79 and Accelerator Pedal Position Sensor 2 G185.
• Switch ignition on.

• Connect Multimeter V.A.G 1526C for voltage measurement to following connector terminals with adapter cables from Connector Test Set V.A.G 1594C.

Terminal 1 + Ground

Terminal 1 + 5

Terminal 2 + Ground

Terminal 2 + 3

Specified value: at least 4.5 V

• Switch ignition off.

If no voltage is present:

• Connect adapter cable, 121-pin V.A.G 1598/31 to engine control module (ECM) wiring harness. The engine control module remains disconnected.

• Check wires between adapter cable, 121-pin V.A.G 1598/31 and 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

Wiring resistance: max. 1.5 Ω

• Also check wires for short circuit to B+ or Ground.
• Also check wires for short circuit to each other.

If no malfunction is detected in the wiring:

• Replace throttle position sensor.

Vehicles with automatic transmission 01M 

• Adapt automatic transmission control module.

Vehicles with automatic transmission 09A 

• Adapt automatic transmission control module.

Continuation for all vehicles 

• Check DTC memory.
• Read readiness code.
• If DTC memory was cleared or engine control module disconnected from voltage supply, readiness code must be regenerated.