Repairs For Each Condition
Repairs for each conditionIf the vehicle exhibits multiple conditions, combine repairs to minimize the repair time.
Condition 1 Repair
1. Obtain the correct, improved parts.
^ Make sure the vehicle production date matches the temperature flap housing part numbers listed in ETKA because of the production date split for the parts. In ETKA the parts are labeled "Housing - Flap Control Box".
^ Improved parts have a dual lip design on the flap doors (Figure 3). The older design utilized a single lip seal on the flap doors. The whistle noise will return if the flap housings with a single lip design are reinstalled.
2. Replace the two temperature flap housings (left and right sides) one at a time as specified at Repair Manual >> Heating, Ventilation and Air
Conditioning >> 87 Air Conditioning >> Removal and Installation >> Left Radiator Housing with Temperature Doors and Right Radiator Housing with Temperature Doors.
Note:
The temperature flap housings are a support structure to the HVAC Unit. Remove only one side of the temperature flap housings at a time. Otherwise, the whistling noises may worsen because of damage to the HVAC unit.
Condition 2 Repair
1. Remove the climate control head unit and the CD changer (or the control unit for the MMI display if equipped with a CAN radio) in order to gain access to the interior of the center stack.
2. Use silver foil 8E0 260 329 and cut out 2 strips of approximately 4 cm in length and 2 cm in width in as seen in Figure 6.
3. Place both strips over the locking tabs of the lower air duct as seen in Figure 7.
4. Temporarily reconnect all center stack control units while performing the verification tests.
5. With the ignition switched on, turn the air distribution to defrost mode, set temperature to HI, and set the blower to level 6 or 7.
6. If the noise has not gone away then recheck the installation of the air duct to the HVAC unit to ensure a proper seal has been made all around the duct. You may need to apply high temp rated duct tape around the entire sealing edge of the duct to remove the whistle noise. The tape should be rated to a minimum of 200°F.
7. Once it has been verified the noise is permanently gone, remount all control units back in to the center stack.
Condition 3 Repair
1. Remove the trim for the MMI screen and the MMI screen.
2. Use rubber plug 8K9 805 673 C to seal the hole. Alternatively, silicone bonder D 176 001 A3 can be used to seal the hole, but be careful not to use too much silicone.
3. Pressing the plug in by hand may not secure it tightly enough. Use a 5 mm Allen socket and small extension.
Firmly press the plug into place.
Condition 4 Repair
The lower two screws holding the temperature flap housings together need to be tightened.
1. Access to the screws is in the passenger footwell area. The glove box must be removed in order to access the screws with the HVAC unit in the car.
2. Use a long T-15 Torx driver to reach the screws. Insert the Torx driver into the areas indicated by the red arrows in Figure 13.
Tighten each of the two screws 90° clockwise with approximately 1NM of torque.
3. Repeat the test and confirm the noise is no longer present.