Audi Workshop Service and Repair Manuals

Testing sender voltage readings

• ‒ Disconnect the 8-pin plug on the throttle valve control part.

• ‒ Switch on ignition.
• ‒ → Measure voltage between contacts 4 and 7 on the 8-pin plug using hand-held multimeter V.A.G 1526.

Specification: at least 4.8 V

If the value is as specified, reconnect the 8-pin plug.

• ‒ Start the engine.
• ‒ Read measure value block (function 08) and select Display Group 98 .

The values in display zone 1 (throttle valve potentiometer voltages) should be between 3.70 and 4.75 volts.

The values in display zone 2 (throttle valve potentiometer voltages) should be between 2.28 and 4.75 volts.

• ‒ If the values are not as specified, switch off the ignition.
• ‒ Connect test box V.A.G. 1598/22 to wiring harness for engine control unit
  => Page 24-13.

• ‒ Disconnect the 8-pin plug on the throttle valve control part.
• ‒ → Test for open circuit between the test box and the 8-pin plug using multimeter V.A.G 1526.
• ‒ Use the multimeter to test the wires for short circuits with each other.

• ‒ Rectify any open circuits and remove any dirt that may be on the contacts. Erase fault memory and perform adaption of throttle valve control part => Page 24-73.
• ‒ If the value is still not as specified, check the throttle valve for dirt and stiffness. Clean if necessary.
• ‒ Repeat adaption of throttle valve control part => Page 24-73.
• ‒ If it is not possible to start the adaption or if the adaption cannot be completed, fit a new throttle valve control part.
• ‒ Perform adaption of throttle valve control part => Page 24-73.
• ‒ If it is not possible to start the adaption or if the adaption cannot be completed, fit a new engine control unit => Page 24-15.
• ‒ If it is not possible to complete the adaption with the new engine control unit, try performing the adaption again with the old throttle valve control part which was removed => Page 24-73.