Audi Workshop Service and Repair Manuals

The throttle valve potentiometer (G69) informs the engine control unit of the position of the throttle valve.

Special tools, testers and auxiliary items

• ◆ Fault reader V.A.G 1551 (or vehicle system tester V.A.G 1552) with cable V.A.G 1551/3
• ◆ Hand multimeter V.A.G 1526 or V.A.G 1526 A
• ◆ Adapter set V.A.G 1594
• ◆ Test box V.A.G 1598/22

• ‒ Connect fault reader V.A.G 1551
  .
• ‒ Switch on ignition.
• ‒ Select "Read measured value block", Display Group 001, engine not running.

• ‒ Check display in display zone 3.

• ‒ Press accelerator pedal down slowly.

If either the initial or the final specification is not attained:

• ‒ Check throttle cable setting

=> 6-cylinder engine (5-valve), Mechanics; Repair group 20; Removing and installing parts of fuel supply system; Servicing throttle mechanism

If the readout does not change or only changes irregularly:

• ‒ Switch off ignition.
• ‒ Unplug connector from throttle valve control part.

• ‒ → Connect multimeter (voltage measurement range) between earth and contact 4 of the connector.
• ‒ Switch ignition on.
• ‒ Specification: approx. 5 V
• ‒ Connect test box V.A.G 1598/22 to wiring harness for engine control unit
  => Page 24-24.

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

• ‒ Rectify any open/short circuit as necessary.

If no wiring fault is detected:

• ‒ Fit a new throttle valve control part (J338).