Owners of other similar Ford vehicles built upon the "Global C" (C1) compact car platform such as the C-Max, Escape, Kuga and Transit Connect may also find these DIY instructions to be useful.

A few compatible replacement cabin air filter elements include the following with their part numbers: Ecogard XC36174, Motorcraft FP70, Wix 24419, TYC 800183P, NPN # 118418-01181745,  ACDelco CF2291 and Cleenaire CAF6196.

A Torx T-15 star bit screwdriver may be needed to access the OEM air filter.

A wet/dry shop vacuum may also be useful for cleaning the existing element if it isn't very dirty and you plan on re-using it.

The foot well panel is held in place by two round black plastic friction fasteners that are attached to yellow pop rivets.

Edit - A thoughtful person sent an email to inform me that there should have been a Torx T-15 star head screw at the bottom of the filter cover. That screw must have been missing on this 2012 Focus.

If your filter cover has a screw on the bottom, loosen it in the counterclockwise direction with a Torx T15 screwdriver.

Squeeze the sides of the black plastic fasteners and slide them straight off the yellow pop rivets.

Remove the dark grey foot well cover and set it aside in a safe place. Behind the panel, you'll see the passenger compartment interior fuse panel.

Squeeze together the two large black plastic tabs near the bottom of the cover to release the clips and pull the access panel away from the blower motor housing. Set the filter cover aside in a safe place.

Gently slide the old filter straight out of the slot in the blower motor housing.

You may need to bend the filter to get it around the various tubes, wires, hoses and other plastic panels that are in the way.

Don't be afraid to bend the filter since it is flexible and won't be easily damaged. Just be sure to carefully route the filter around the obstructions and don't cause any rips or tears if you plan on re-using it.

If the old filter is relatively clean, just tap out any large debris and remove the fine dust with a wet/dry vacuum cleaner.

If the old element is dark grey or black and clogged with dirt, dust, hair, insects, leaves, pollen and twigs, it should be replaced with a brand new unit. If you have severe allergies, consider purchasing an activated carbon filter.

I recommend buying the Ecogard XC36174 cabin air filter since it has excellent reviews on Amazon.

You will need to compress the pleats or bend the filter to get it around the fuse panel and under the bottom of the dash board. Do not use excessive force to avoid tearing or puncturing the filter.

Insert the top edge of the rectangular black plastic filter cover in place first.

If your cabin air filter access panel was equipped with a screw at the bottom of the cover, tighten it in the clockwise direction with the Torx T15 star bit screwdriver. (The screw was missing on this 2012 Focus sedan.)

Double check that the filter cover is securely in place before moving on to the next steps.

Enjoy the fresh clean air from your A/C system!

For more, check out my other Ford Focus Repair & Maintenance Guides.