Volkswagen Workshop Service and Repair Manuals

Matching 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.

Matching sequence must be performed on vehicles 08.95 ▸ if:

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

Special tools, 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 01-5 .)

• ‒ 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.

Matching has been performed successfully.

To store the values:

• ‒ Switch off ignition.

Note:

If the basic setting of the control unit is interrupted, the cause could be one of the following:

• ◆ Throttle valve cannot reach the mechanical stop because of contamination e.g. oil deposits or an incorrectly adjusted throttle cable.
• ◆ Battery voltage too low.
• ◆ Throttle valve control unit or wiring is defective. Checking => Page 24-34 .

After a termination the fault "01165 fault in basic setting" is stored in fault memory. When next switching on ignition the basic setting is automatically performed again.

• ‒ End the engine basic setting by pressing the⇒ key.
• ‒ Check throttle valve control unit specifications in display zone 5, => Page 01-63 , evaluating measured value block. If specifications are not attained, repeat adaption.
• ‒ Press keys 0 and 6 for the function "End output" and confirm entry with the Q key.