Volkswagen Workshop Service and Repair Manuals

Special tools, workshop equipment, test and measuring appliances and auxiliary items required

• ◆ V.A.G 1526 A Hand multimeter or multimeter V.A.G 1715
• ◆ V.A.G 1594 A Adapter set
• ◆ V.A.G 1598/18 Test box
  for 68-pin control unit
• ◆ V.A.G 1598/22 Test box
  for 80-pole control unit
• ◆ Fault reader V.A.G 1551 or vehicle system tester V.A.G 1552 with cable V.A.G 1551/3
• ◆ Current flow diagram

Function

The accelerator pedal position sender is located on accelerator pedal and passes driver's requirement (pedal position) on further to the control unit.

Check conditions

• ● Fuses must be OK.
• ● The battery voltage must be at least 11.5 V.

Test sequence

• ‒ Connect fault reader V.A.G 1551 (V.A.G 1552) and with ignition switched on select engine electronics control unit with the "Address word" 01:

=> Repair group 01; Self-diagnosis; Connecting fault reader V.A.G 1551 and selecting engine electronics control unit

• ‒ Press keys 0 and 8 for the function "Read measured value block" and confirm entry with Q key.

• ‒ Press keys 0, 0 and 2 for "Display group number 2" and confirm entry with Q key.

• ‒ Display zone 2:
  The accelerator pedal position figure must increase continuously.
       Specification at full throttle position: 100.0 %
• ‒ Display zone 3:
  The centre position must change to 0.
       Display: 0 0 0

End specification value not achieved:

• ‒ Adjust accelerator pedal position sender
  =>Page 20-23

Display does not change or is erratic:

• ‒ Check accelerator pedal position sender wiring as follows:
• ‒ Press the ⇒key.

• ‒ Press keys 0 and 6 for the function "End output" and confirm entry with the Q key.
• ‒ Switch off ignition.
• ‒ Remove cover in footwell (driver's side).
• ‒ → Disconnect 6-pin connector -1- for accelerator pedal position sender.

• ‒ → Measure sender resistance between connector contacts 1+3.
       Specification:
       Accelerator pedal in idling speed position: 1.0...1.5 kω
       Accelerator pedal in full throttle position: 1.5...2.5 kω
• ‒ Measure resistance between connector contacts 4+6.
       Specification:
       Accelerator pedal in idling speed position: max.1.5 kω
       Accelerator pedal depressed: ∞ ω

If the specifications are not obtained:

• ‒ Replace accelerator pedal position sender (G79)
  =>Page 20-20 , item 2 .

If the specifications are obtained:

Engine code AGD (with 68 pin control unit)

• ‒ → Connect test box V.A.G 1598/18 to control unit wiring harness -1-. The engine control unit -2- remains disconnected.

• ‒ → Check wiring between test box and connector for open circuit according to current flow diagram.
       Contact 1+ socket 15
       Contact 2+ socket 57
       Contact 3+ socket 55
       Contact 4+ socket 65
       Contact 5+ socket 62
       Contact 6+ socket 33
       Wire resistance: max. 1.5 ω

Engine codes AGD (with 80-pin control unit), AHG, AKU

• ‒ → Connect test box V.A.G 1598/22 to control unit wiring harness.

• ‒ → Check wiring between test box and connector for open circuit according to current flow diagram.
       Contact 1+ socket 24
       Contact 2+ socket 11
       Contact 3+ socket 23
       Contact 4+ socket 12
       Contact 5+ socket 8
       Contact 6+ socket 25
       Wire resistance: max. 1.5 ω

Continued for all engine codes

• ‒ Additionally check the wiring for short to battery positive or earth.
• ‒ Additionally check wires for short to one another.

If no fault is detected in the wiring:

• ‒ Renew engine control unit:

=> Repair group 23; Renewing, coding and adapting engine control unit; Renewing engine control unit