Audi Workshop Service and Repair Manuals

Testing sender voltage readings

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

• ‒ Switch the ignition on.
• ‒ → 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.
• ‒ Select Read measured value block (function 08) and 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 positioner 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
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• ‒ Disconnect the 8-pin connector on the throttle valve control unit.
• ‒ → Test for continuity between the test box and the 8-pin connector 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 adaptation of throttle valve control unit .
• ‒ If the value is still not as specified, check the throttle valve for dirt or stiffness and clean if necessary.
• ‒ Repeat adaptation of throttle valve control unit .
• ‒ If it is not possible to start the adaptation or if the adaptation cannot be completed, fit a new throttle valve control unit.
• ‒ Perform adaptation of throttle valve control unit .
• ‒ If it is not possible to start the adaptation or if the adaptation cannot be completed, fit a new engine control unit => Page 24-10.
• ‒ If it is not possible to complete the adaptation with the new engine control unit, try performing the adaptation again with the old throttle valve control unit that was removed => Page 24-69.