Volkswagen Workshop Service and Repair Manuals

Adapting teaches the engine control unit (with ignition switched on and engine not running) the throttle valve control part stop positions and a comparison graph between throttle valve potentiometer and throttle valve positioner sender.

Adapting sequence must be performed if:

• ◆ The throttle valve control unit is removed and installed
• ◆ The throttle valve control unit is renewed
• ◆ If when installing another engine another throttle valve control unit is installed

Special tools, workshop equipment, testers, measuring instruments and auxiliary items required

• ◆ Fault reader V.A.G 1551 or vehicle system tester V.A.G 1552 with cable V.A.G 1551/3

Test conditions

• ● No faults must be stored in fault memory
  , interrogating fault memory
• ● The battery voltage must be at least 11.5 V.
• ● All electrical consumers, e.g. lights and rear window heating must be switched off
• ● The throttle valve must be at idling speed position.
• ● The cruise control system must be functioning correctly if installed.

Work sequence

• ‒ Connect the fault reader V.A.G 1551 (V.A.G 1552). Then switch ignition on and select engine control unit with the "Address word" 01.
  (Connecting fault reader and selecting engine control unit => Page 01-4 .)

• ‒ Press keys 0 and 4 for the function "Introduction of basic setting" and confirm entry with Q key.

• ‒ Press keys 0, 9 and 8 for "Display group number 98" and confirm entry with Q key.

After pressing the Q-key the throttle valve positioner is driven to Min., Max. and five intermediate positions and the relevant throttle valve angle stored in non-volatile memory. This procedure takes approx. 10 seconds. The throttle valve then remains in the start position for a brief period then closes.

The adaption of the engine control unit to the throttle valve control part is now complete.

Note:

If one of the following readouts appears on the display, this means that the adaption has not been completed successfully:

Note on display zone 3:

Relevance of figures in 8-digit number block for throttle valve control part operating condition:

Note on display zone 4:

Significance of figures in 2-digit number block for the throttle valve control part matching condition:

Notes:

If the adaption of the control unit is interrupted, the reason could be one of the following:

• ◆ The requirements for the adaption of the engine control unit to the throttle valve control part have not been met. For a list of the requirements, see Fault Table, fault code 01087.
• ◆ The throttle valve cannot reach the mechanical idling stop because of a build-up of dirt (e.g. oil carbon deposits) or an incorrectly adjusted throttle cable.
• ◆ Throttle valve control part or wiring is defective.

After an interruption the fault "Basic setting not completed; Implausible signal" is recorded in fault memory.

The next time the ignition is switched on the engine control unit will try to perform the adaption again.

• ‒ Terminate engine basic setting by pressing the⇒ button.
• ‒ Press keys 0 and 6 for the function "End output" and confirm entry with the Q key.
• ‒ Switch off ignition.

Note:

The ignition must remain switched off for at least 15 seconds so as to store the basic setting.

• ‒ Check the operating mode of the throttle valve control part => Page 24-39