Throttle Position Sensor G79 and Accelerator Pedal Position Sensor 2 G185, Checking

Special tools, testers and auxiliary items required 

• Multimeter.
• Wiring diagram

Test requirement 

• The Motronic Engine Control Module (ECM) J220 fuses OK.
• Battery voltage at least 12.5 volts.
• All electrical consumers such as, lights and rear window defroster, switched off.
• Vehicles with automatic transmission, shift selector lever into position "P" or "N".

• A/C switched off.
• Ground (GND) connections between engine/transmission/chassis OK.

Test procedure 

• Perform a preliminary check to verify the customers complaint. Refer to → Preliminary Check .

Fig 1: Removing Steering Column Cover

Courtesy of VOLKSWAGEN UNITED STATES, INC.

• Release the tabs - arrows  - and remove the steering column cover.

Start diagnosis 

Fig 2: Identifying Throttle Position Sensor G9/Throttle Position Sensor G88 6-Pin Electrical Harness Connector

Courtesy of VOLKSWAGEN UNITED STATES, INC.

• Disconnect the Throttle Position (TP) Sensor G79/Accelerator Pedal Position Sensor 2 G185 electrical harness connector - 2  -.

Checking voltage supply and wiring 

• Switch the ignition on.

Fig 3: Identifying 6-Pin Electrical Harness Connector & Terminals

Courtesy of VOLKSWAGEN UNITED STATES, INC.

• Using a Multimeter, check the following wiring connections for voltage.

• Switch the ignition off.

If the specification is not obtained:

If the manufacturers test box is being used, perform the following step.

• Install the test box VAG1598/31. Refer to 24 MULTIPORT FUEL INJECTION (MFI) .

If the manufacturers test box is not being used, perform the following step.

• Remove the Motronic Engine Control Module (ECM) J220. Refer to → Motronic Engine Control Module (ECM) J220, Replacing .

Fig 4: Identifying 6-Pin Electrical Harness Connector & Terminals

Courtesy of VOLKSWAGEN UNITED STATES, INC.

• Using a Multimeter, check the Throttle Position (TP) Sensor G79/Accelerator Pedal Position Sensor 2 G185 electrical harness connector terminals to the Motronic Engine Control Module (ECM) J220 electrical connector for resistance.

Specified value: 1.5 Ω max.

If the specification is not obtained:

• Check the wiring for a short circuit to each other, Battery (+), and Ground (GND).
• Check the electrical harness connector for damage, corrosion, loose or broken terminals.
• If necessary, repair the faulty wiring connection.

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

• Replace the Throttle Position (TP) Sensor G79/Accelerator Pedal Position Sensor 2 G185. sensors are contained within one housing.

If no malfunction is detected in the wiring and if the voltage supply was not OK:

• Erase the DTC memory. Refer to → Diagnostic Mode 04 - Reset/Delete Diagnostic Data
• Perform a road test to verify repair.

If the DTC does not return:

Repair complete, Generate readiness code. Refer to → Readiness Code Description .

• End diagnosis.

If the DTC does return and no malfunction is detected in the wiring and the voltage supply was OK:

• Replace the Motronic Engine Control Module (ECM) J220. Refer to → Motronic Engine Control Module (ECM) J220, Replacing .
• Assembly is performed in the reverse of the removal.

Final procedures 

After repair work, the following work steps must be performed in the following sequence:

1. Check the DTC memory.
2. If necessary, erase the DTC memory. Refer to Diagnostic Mode 04 - Reset/Delete Diagnostic Data .
3. If the DTC memory was erased, generate readiness code. Refer to Readiness Code Description .

End of diagnosis