Volkswagen Workshop Service and Repair Manuals

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

• ◆ Fault reader V.A.G 1551 with cable V.A.G 1551/3

Removing

• ‒ First print out the control unit identification and thereby the previous control unit coding as follows:
• ‒ 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 .)

• ‒ Print out the control unit identification by pressing the fault reader print button.
• ‒ Press the ⇒key.
• ‒ Press keys 0 and 6 for the function "End output" and confirm entry with the Q key.

• ‒ Switch off ignition.
• ‒ Remove windscreen wiper arms and the cover for plenum chamber:

=> Electrical system; Repair group 92; windscreen wiper system; removing and installing windscreen wiper system

• ‒ Release connector from control unit and pull off.

• ‒ → Unclip the control unit from the retaining frame -arrows-.

Installing

• ‒ Place the new control unit into the retaining frame.
• ‒ Install control unit connector and lock.
• ‒ Check the previous coding and the coding of the new control unit => Page 24-124 .
• ‒ Erase the learnt values and adapt the engine control unit again=> Page 24-128 .

Engine code: ARC

• ‒ Adapt new control unit to the electronic immobilizer => Page 24-133

Engine code: AVY

=> Electrical system; Repair group 01; Immobilizer self-diagnosis; Adaption following renewal of engine control unit

• ‒ Interrogate fault memory, if necessary, repair any faults and then erase fault memory => Page 01-20 , interrogating and erasing fault memory.
• ‒ Perform idling speed check
  => Page 24-91 .
• ‒ Carry out test drive.

• During the road test the following operating conditions must be fulfilled:
• ‒ The coolant temperature must exceed 80 °C .
• ‒ When the temperature is reached, the operating conditions
       Idling
       Part throttle
       Enrichment
       Full throttle
       Overrun
  must be attained several times.

• ‒ Again interrogate the control unit fault memory.