Since quite a few people have had issues with their heater blowing air at full blast, I decided to make a quick guide of how to replace the heater resistor.
The heater resistor is located in the passenger's foot-well behind the glovebox.
First of all, you need to remove the sound insulation cover under the glovebox. To do this, you need to undo two screws (philips head) located where the yellow arrows are pointing. You can see a close up of the screws highlighted with the yellow circle in the next image. Also remove the plastic cover highlighted in the green circle. You will see why later.
Remove the cover and you can now see the connector plugging in the resistor.
You need to remove these two screws securing the resistor. The bottom screw is very easy to undo, but the top one is harder to get to.
Undo the two screws (marked by the red arrows) and pull out the glovebox
Undo the three screws (yellow circles) and undo the 10mm bolt (red circle)
You can now pull the main console forward just enough to gain access to the top screw
Undo it and pull out the resistor.
The part number of the resistor is 30864189
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