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Removing and installing anti-theft engine control unitJ623 (engine codes BUD and CGGB) > < Engine control unitJ623

Polo Mk5

Removing and installing anti-theft engine control unitJ623
Removing and installing anti-theft engine control unit -J623-
Special tools and workshop equipment required
   
t  Hot air blower from wiring harness repair set -VAS 1978 B-
t  Nozzle attachment from wiring harness repair set -VAS 1978 B-
If you wish to renew the engine control unit, connect the → Vehicle diagnostic testerVehicle diagnostic, testing and information system and carry out the guided function „Renew control unit“.
Removing
–  Remove windscreen wiper arms and cover for plenum chamber → Electrical system; Rep. gr.92.
  Note
The shear-head bolt threads are coated with locking compound. Heating the shear-head bolt with a hot air blower releases the locking effect of the locking compound.
  Caution
Cover brake hose and cable to brake fluid container in order to avoid damage.
Perform settings on hot air blower -4- as shown:
  W00-0447
–  Turn temperature setting potentiometer -2- to maximum heat output (600 °C).
–  Set two-stage switch for volume of air -3- to position 3.
  WARNING
When shear-head bolts are heated up, parts of the protective housing will be subjected to a large amount of heat. Wear protective gloves to avoid possible injury.
–  Place nozzle of hot air blower close to shear-head bolt.
–  Switch on hot air blower and heat bolt for about 20 to 25 seconds.
–  Unscrew shear-head bolt using mole grips on bolt head.
The procedure for the second shear-head bolt is identical.
–  Push the clips of the protective housing in the plenum chamber together and unhook it from the plenum chamber partition panel.
–  Pull the protective housing off the engine control unit.
–  Release connectors on engine control unit and pull off connector.
Installing
–  Fit connectors and lock in position.
–  Push the protective housing over the engine control unit.
–  Install cover of protective housing using new shear-head bolts.
–  Tighten shear-head bolts evenly until head shears off.
–  Hook the protective housing into the plenum chamber partition panel and push the clips into the openings.
–  Install windscreen wiper arms and the plenum chamber cover → Electrical system; Rep. gr.92
–  If engine control unit is renewed, clear learnt values and adapt engine control unit → Vehicle diagnostic tester„Guided functions“.
–  Read fault memory, repair faults if necessary and then clear fault memory → Vehicle diagnostic tester„Guided fault finding“.
–  The readiness code must be generated if the fault memory has been erased.
–  Carry out a road test.
–  Read control unit fault memory again.
  A24-0476

Removing and installing anti-theft engine control unitJ623 (engine codes BUD and CGGB) > < Engine control unitJ623