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On setting 3 and 4 of the fan I get a highly irritating rattle. Can't figure it out! Comes from passenger side footwell, and is causing a mild to severe case of insanity. Do I need to pull the dash out...?

I had something similar to this in another vehicle, it was a leaf in the fan box. Shoot Dann a mess, he may be able to help you with a 'how to'
Greg.

if it sounds like a bicycle wheel with a card in it (constant ticking noise) you've likely got some debris caught in the fan.
I have just cleaned out mine today and installed a foam filter to stop that stuff happening to me..

if it is debris in the fan, (hopefully), you can get to it from within the engine bay (sort of)

pop off the wiper caps and remove the wipers
pry off the windscreen cowling caps and remove the windscreen cowling
remove the black cowling on the passenger side


the HVAC intake grill will now be visible.
remove the grill (kinda destructive part)... I used a long nose pliers and pulled the grill grating off.
This grill grating you can get as 'body kit mesh' from supercheap or the likes but i didnt bother replacing that.
The fan is beneath this grill.

You can vacuum out the debris from the fan.
Use a long long flat headed screwdriver to lift up various bits of twigs and leaf matter and suck it up via the vacuum cleaner, as the dome in the middle of this fan will prevent the vacuum tip reaching the debris.

Once the fan is clear, i then used a compressor to blow material not visible further into the fan, pushing the material well away from the blades..

The upright tunnel that the mesh was on, i used a pair of pliers to gently "out-lip" the 3 of the edges. (i couldnt reach the cabin side lip)

I installed a flat filter foam sponge folded over the intake and secured it with 3x 30cm cable ties serialed together.
(a 30x30x2.5cm air filter piece from Clark Rubber will be plenty)
The cable ties and sponge wont come loose because of the out-lipping of the upright tunnel thingy..




I then trimmed the excess sponge, making sure to make clearnance from the wiper control arm.

then put the cowlings back on..

Fingers crossed your fan will be quiet now.
if it is, great - with the filter, debris wont get in there again.

All up, this took me about 2 hours, including me plastidipping my wiper arms and cowlings.

Before i did this, i had random noises from my fan at the 4th setting, from the card-in-the-bike-spoke sound to various weird sounds.. Now it sounds like it should..

Hope this helps.

You can also get to the heater and fan assembly from under the dash. Just remove the the glovebox.

Quick tip for getting a vacuum in to trick spots, get some hose and put it in the end of the vacuum hose and wind tape around it. You can shove the hose in to small spaces.

Thanks for this. I've had the same problem going on a year now.