Volkswagen Workshop Service and Repair Manuals

Note:

• ◆ Final control diagnosis must be carried out with engine stationary.
  .
• ◆ For results to be definitive, final control diagnosis must be carried out at an ambient temperature of at least 12°C as displayed on control and display panel. Operation and function of control and display panel
• ◆ Climatronic does not self-adjust during final control diagnosis.
• ◆ If necessary, final control diagnosis can be repeated several times.
  

Initiating final control diagnosis

• ‒ Connect fault reader V.A.G 1551 and select Air cond./Heating electronics (address word 08) .

• ‒ Press keys -0- and -3- (03 selects "Final control diagnosis" function).

• ‒ Confirm input with Q key.

The following tests are carried out:

• ◆ Read out in display of control and display panel -E87-
• ◆ Functional test of the 3 positioning motors
• ◆ Current track to fresh air blower -V2- is tested
• ◆ Current track to magnetic coupling -N25- is tested

• ‒ If "Function is not recognized or cannot be carried out at the moment" appears in display, final control diagnosis has been concluded.
• ‒ Press ⇒ button.

Note:

After completing final control diagnosis, interrogate fault memory => Page 01-8

Check display in control and display panel -E87-

→ Vehicles up to 07.95

→ Vehicles from 08.95

Note:

• ◆ All segments must appear in display. If not, renew control and display panel.
• ◆ After a period in excess of 20 seconds the display will change.
  .

Test of positioning motors

The positioning motors:

• ◆ Temperature flap positioning motor -V68-
• ◆ Central flap positioning motor -V70-
• ◆ Air flow flap positioning motor -V71-

will be moved once over their complete range. The first half of the movement the motors will be fully activated, for the rest driven in stages.

The movement will be completed in approx. 30 seconds and the following end positions attained:

     1)     If necessary check and adjust end position of temperature flap positioning motor -V68- when installed in vehicle => Page 87-70

     2)     Air flow to windscreen

     3)     The position of the air flow flap can be checked with the dust and pollen filter removed.

Note:

If when subsequently interrogating the fault memory (=> Page 01-8 ) no fault is recognized, even though the end positions were not attained, then the appropriate positioning motor or the air flap must be checked for mechanical damage.

Testing the current track to fresh air blower -V2-

• ◆ During the final control diagnosis the fresh air blower is activated with 3 different voltages. Should a fault be detected in the fresh air blower current track, it will be stored in the fault memory.

Testing the current track to magnetic coupling -N25-

• ◆ The current track is tested from Climatronic control unit -J255- connection T28a/15 to the air conditioner pressure switch -F129-. Should a fault be detected, it will be stored in the fault memory.

Note:

If during the subsequent interrogation of the fault memory (=> Page 01-8 ) no fault is detected, even though the magnetic coupling is not being activated during cooling operation, then check wiring from air conditioner pressure switch -F129- via -F163- (not on vehicles with 2-speed radiator fan) and -J293- to magnetic coupling using current flow diagram.