Volkswagen Workshop Service and Repair Manuals

First of all, the old learnt values are erased. This is necessary to neutralise learnt values, which may be at the limit. During adaption (ignition switched on, engine not running), the engine control unit learns various positions of the throttle valve control part and exhaust gas recirculation valve. These positions are stored in the control unit.

Adapting sequence must be performed if:

• ◆ The voltage supply is interrupted
• ◆ The throttle valve control unit is removed and installed
• ◆ The throttle valve control unit is renewed
• ◆ The engine control unit is replaced
• ◆ 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 1551/3A

Check conditions

• ● Ignition on, engine not running
• ● No faults must be stored in fault memory , interrogating and erasing fault memory.
• ● The battery voltage must be at least 11.5 V.
• ● If the vehicle is equipped with an air conditioning system, this must be switched off.
• ● All electrical consumers, e.g. lights and rear window heating must be switched off.
• ● The throttle valve must be at idling speed position (The accelerator must not be operated during the test).
• ● Coolant temperature must be 5...50 °C =>display group 04, display zone 3.

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 01-9 .)

• ‒ Press keys 0 and 4 for the function "Initiating basic settings" and confirm entry with Q key.

• ‒ Press keys 0, 6 and 0 for the "Display group number 60" and confirm entry with Q key.

After pressing the Q key the throttle valve positioner is switched so that it is not supplied with voltage at start of test.

In this condition the throttle valve is pulled into an emergency running position by a mechanical spring in the throttle valve control part. The values that both angle senders provide in the emergency running position are stored by the engine control unit.

Thereafter the throttle valve is opened a predetermined value. If this value is achieved, the throttle valve is again switched so that it is not supplied with voltage. Now the mechanical spring must pull the throttle valve to the previously learnt emergency running position within a predetermined period (spring test).

Then the throttle valve is closed by the throttle valve positioner and the values, which are supplied by the angle senders in the throttle valve control part are stored by the engine control unit.

If the engine control unit switches the throttle valve positioner so that it is without voltage during normal operation, this is indicated by the increased and hunting idling speed. The engine reacts slowly to accelerator changes.

Adapting has been performed successfully.

• ‒ Terminate engine basic setting at earliest after 30 seconds by pressing the⇒ key.

Only engines which conform to EU 4 standard (engine code AKP, AUC, AUD)

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

• ‒ Press keys 0, 7 and 4 for the "Display group number 74" and confirm entry with Q key.

Adapting has been performed successfully.

• ‒ End the engine basic setting by pressing the⇒ key.

Continued for all engine codes

• ‒ Press keys 0 and 6 for the function "End output" and confirm entry with the Q key.

To store the values:

• ‒ Switch off ignition for at least 25 seconds (control unit run-on).
• ‒ On vehicles with automatic gearbox, the gearbox control unit must be adapted.
• ‒ Press keys 0 and 6 for the function "End output" and confirm entry with the Q key.

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:

• ◆ Battery voltage too low.
• ◆ Throttle valve control unit or wiring is defective. Check => Page 24-46 .
• ◆ Exhaust gas recirculation valve or wiring is defective.

After an interruption a fault is stored in fault memory. When next switching on ignition the basic setting is automatically performed.