Test sequence

• Connect VAG1551 or VAG1552 scan tool.
  1. See VAG1551 SCAN TOOL (ST), CONNECTING
• Switch ignition on.

• Press buttons -0- and -1- to insert the "Engine Electronics" address word 01.

Indicated on display

Fig 1: Scan Tool Display - Checking Throttle Position (TP) Sensor (1 Of 6)

• Press buttons -0- and -8- to select "Read Measuring Value Block" function 08, and press -Q- button to confirm input.

Indicated on display

Fig 2: Scan Tool Display - Checking Throttle Position (TP) Sensor (2 Of 6)

• Press buttons -0-, -0- and -2- to input display group no. 2 (002), and press -Q- button to confirm input.
• Refer to display field 2 (accelerator pedal position).
  Fig 3: Scan Tool Display - Checking Throttle Position (TP) Sensor (3 Of 6)

  

  Specified display: 0.0 % (accelerator pedal not operated)

• Refer to display field 3.
  Fig 4: Scan Tool Display - Checking Throttle Position (TP) Sensor (4 Of 6)

  

  Specified display: 0 1 0 (accelerator pedal not operated)

• Press accelerator pedal down slowly.

  Specified displays (accelerator pedal fully depressed):

  • Display field 2 must increase steadily to 100 %
    Fig 5: Scan Tool Display - Checking Throttle Position (TP) Sensor (5 Of 6)

    
  • Display field 3 must change to: 0 0 0
    Fig 6: Scan Tool Display - Checking Throttle Position (TP) Sensor (6 Of 6)

    

Note for vehicles with automatic transmission ONLY: 

The kick down switch actuation point must be distinctly felt before the pedal reaches Wide Open Throttle (WOT) position.

If the displays are not as specified:

• Adjust throttle position sensor.
  1. See ADJUSTING 

If displays do not change or are irregular:

• Check throttle position sensor -G79- as follows:
• Switch ignition off.
• Disconnect throttle position sensor harness connector.
  1. See DIESEL DIRECT FUEL INJECTION (DFI) SYSTEM COMPONENTS, OVERVIEW 
• Switch multimeter to resistance range.

• Measure resistance between sensor terminals 1 and 3 using adapters from VW1594 connector test kit.
  Fig 7: Identifying Throttle Position Sensor Harness Connector Terminals

  

  Accelerator not depressed (closed throttle position):

  • Specification: 1000 to 1500 ohms (ohm)

  Accelerator depressed (wide open throttle):

  • Specification: 1500 to 2500 ohms (ohm)

If resistance is not as specified:

• Replace throttle position sensor -G79-.
• Display readiness code, see READINESS CODE, DISPLAYING .

If DTC memory was erased:

• Create readiness code again, see READINESS CODE, SETTING (UP TO M.Y. 1997) .

If specifications are obtained:

• Switch ignition off.
• Disconnect throttle position sensor harness connector.
  1. See DIESEL DIRECT FUEL INJECTION (DFI) SYSTEM COMPONENTS, OVERVIEW 
• Connect VAG1598/18 test box to Diesel DFI ECM connector.
  Fig 8: Connecting VAG1598/18 Test Box To Diesel DFI ECM Connector

  

• Check following wiring connections for open circuits and/or short circuit to positive or negative:
  • Terminal 1 to test box socket 15
  • Terminal 2 to test box socket 57
  • Terminal 3 to test box socket 55
  • Terminal 4 to test box socket 65
  • Terminal 5 to test box socket 62
  • Terminal 6 to test box socket 33
  Fig 9: Identifying Throttle Position Sensor Harness Connector Terminals

  
• Repair any open or short circuit as necessary.

If neither an open or short circuit exists

• Replace Diesel DFI ECM -J248-, see item  3 .
• Display readiness code, see READINESS CODE, DISPLAYING .

If DTC memory was erased:

• Create readiness code again, see READINESS CODE, SETTING (UP TO M.Y. 1997) .