HVAC control unit removal

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HVAC control unit

To remove the HVAC control unit the center console must be removed as well. Unlike the radio and multi-information display (MID), the HVAC control unit is mounted on the backside of the center console and its screws are only accessible from the back. Removing the center console sounds worse than it actually is – unless really clumsy it should take less than ten minutes. The location and amount of the screws that hold the center console differ with the style of center console and the car's transmission. On a center console with wood trim three screws are hidden inside the opening where the multi-information display is installed. To reach those the MID must be removed. The regular plastic center console has two screws behind blind caps just above the MID location. Be careful when removing these caps to avoid damage to the plastic. Although not strictly required for the removal of the plastic center console, it is recommended to remove the MID here too. It makes handling the center console a lot easier.

The multi-information display is secured in the center console with retaining tabs – three small ones on top of the unit and one wide tab on the bottom. The bottom tab must be pressed to remove the MID. To gain access to this tab it is necessary to remove the radio. Once the radio is out and disconnected, reach in the opening and firmly press the retaining tab on the bottom of the unit while simultaneously pushing the MID towards you. Usually it slides out without much effort but in some cases the top retaining tabs block it. Just push harder and carefully wrench the unit out. The MID is connected with a single cable. Release the connector's locking lever and unplug it. All connectors behind the center console fit in one direction only and the shape or color makes clear where they should connect to. There is no real need to label the connectors although it never hurts of course.

The remaining screws are underneath the shifter's leather boot. Grab the boot on both sides and pull up. It just clicks softly in the center console and should come off quite easily. Then grab the shift knob with both hands and pull hard and straight up. This will require some force! Avoid accidently hitting something – like your face – when the shift knob comes off the shift lever. In cars equipped with manual transmission there is only one screw in the opening – undo it. In case of an automatic transmission, the shifter plate must be removed as well. There is a fragile pin through the shift lever for the older automatic transmission without Steptronic. The pin is held in position by a clip on the driver's side. Press the clip upwards until the pin can move. Newer Steptronic transmissions do not have this pin. Now undo the two remaining screws holding the shifter plate and lift it. Unplug the connector attached to the transmission switch and remove the shifter plate from the center console. The metal shift lever has sharp edges – wrap a small soft towel around it to avoid damaging other parts.

Make a picture of the center console or write down the location of each switch surrounding the shifter for the installation later on. Normally the wiring harness points out what goes where but a photograph or drawing removes all doubt. Lift the center console a bit and push the center console switches out from underneath. Press the small retaining tabs on each connector and pull to unplug.

If the car is equipped with the factory hands-free mobile phone, its microphone must be removed before the center console can be taken out. The microphone is the small grate left from the multi-information display. Reach in through the MID opening, push the microphone out of the center console and unplug it. If you did not remove the radio and MID, lift the center console until you can reach behind it and push the microphone out that way. Then flip the center console and disconnect the radio and MID. The last thing that ties down the center console to the car is the wiring harness to the HVAC control unit: A large blue connector with a locking lever and a small connector just above that. Unplug both and remove the center console from the car.

The HVAC control unit is secured to the center console from the rear by four screws – two on the bottom and one on each side. Undo all four screws to remove the unit.