1. Disconnect the wire from the negative terminal of the battery.
2. Remove the central instrument panel trim (see "Removal and installation the instrument panel").
3. Remove the two screws securing the heating and air conditioning control unit to the instrument panel.
4. Pull the control unit out of the socket in the instrument panel and disconnect the wiring harness connector from it.
5. Under the instrument panel, remove the cable sheaths from the holders on the heater body and disconnect the air flow distribution flap drive cable from the levers (to the left of the heater, with a green casing)...
6. ...recirculation flap drive cable (to the left of the heater, with a black casing)...
7. ...cable for the air temperature control flap drive supplied to the passenger compartment (to the right of the heater, with a white casing) and remove the air conditioning and heating system control unit.
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Note: Remember the location of the cables by the color of their sheaths so that when reinstalling them you do not mix up the heater levers for connecting them.
8. Install the HVAC control unit and all removed parts in the reverse order of removal.