Audi Workshop Service and Repair Manuals

Special tools and workshop equipment required

• ◆ V.A.G 1526 A
• ◆ V.A.G 1594 A
• ◆ V.A.G 1598/22
  (Vehicles ä 07.99)
• ◆ V.A.G 1598/31
  (Vehicles 08.99 ä)
• ◆ VAS 5051 with VAS 5051/1

• or

• ◆ V.A.G 1551 with V.A.G 1551/3 A

Test sequence

• ‒ → Connect the vehicle diagnostic, test and information system VAS 5051 or fault reader V.A.G 1551 and select engine electronics control unit by entering address word "01. When doing this the ignition must be on

=> TDI injection and glow plug system (4-cyl. ) 07.97 ä 07.99; Repair group 01; Self-diagnosis

=> TDI injection and glow plug system (4-cyl.) 08.99 ä; Repair group 01; Self-diagnosis

=> TDI injection and glow plug system (4-cyl. unit injector); Repair group 01; Self-diagnosis

• ‒ Enter "08" to select the function "Read measured value block" and confirm entry with Q key.

• ‒ Press keys 0, 0 and 2 for "Display group number 002" and confirm entry with Q key.

• ‒ Check display in display zone 2.
• ‒ Specification: 0.0 % (accelerator not depressed)
• ‒ Check display in display zone 3.
• ‒ Specification:
  0 1 0 (accelerator not depressed)
  0 0 0 (accelerator depressed)
• ‒ Press accelerator pedal down slowly.

Vehicles with manual gearbox

• ‒ Check display in display zone 2.
• ‒ Specification: the value should increase steadily to 100 % (accelerator fully depressed).

Vehicles with automatic gearbox

• ‒ Specification: the pressure point of the kick-down switch should be clearly noticeable before reaching the full-throttle stop.

All models

If the specifications for the initial and/or final readouts are not obtained:

• ‒ Test free travel of module, renew accelerator pedal module if necessary.

If the display does not change or only changes irregularly:

Testing internal resistance

• ‒ Switch off ignition.
• ‒ Remove accelerator pedal module and unplug connector for accelerator position sender -G79.

• ‒ → Connect multimeter (resistance measurement range) as follows:

    1)    Only on vehicles with automatic gearbox.

If the specifications are not obtained:

• ‒ Renew accelerator pedal module with accelerator position sender -G79.

Checking wiring connections

• ‒ Switch off ignition.
• ‒ → Remove rubber seal from plenum chamber in direction of arrow.
• ‒ Remove plenum chamber cover -1- from the front.

• ‒ → Remove cover for electronics box in plenum chamber -arrows-.

• ‒ → Carefully lever off the retainer bar with a screwdriver -arrow-.
• ‒ Release catches and unplug control unit connectors.

Vehicles ä 07.99:

• ‒ → Connect test box V.A.G. 1598/22 to the connectors which have been unplugged from the engine control unit (control unit remains disconnected).

Vehicles 08.99 ä:

• ‒ → Connect test box V.A.G 1598/31 to unplugged connectors for engine control unit (control unit remains disconnected). Also connect earth clamp of test box to earth.

All models

• ‒ Remove storage compartment (shelf) on driver's side.

=> General body repairs, Interior; Repair group 68; Storage compartments, covers; Removing driver's storage compartment

• ‒ Unplug connector for accelerator position sender -G79 (located in footwell on accelerator pedal).

• ‒ → Test for open circuit and short to positive or earth in the following wiring connections:

• ‒ Rectify any open/short circuit as necessary.

=> Current flow diagrams, Electrical fault finding and Fitting locations binder