DIY Cabin Air Filter for 2020 CX-5 - musty smell in AC

ClearTheCode admin answer:

A musty smell from your AC is a classic sign that your cabin air filter needs replacement. It's a relatively simple DIY task on most Mazda CX-5 models, including your 2020 Carbon Edition.

Here's a general guide:

1. Locate the Filter: The cabin air filter in your CX-5 is typically located behind the glove compartment. You'll need to open the glove box and usually unclip or remove a few screws/dampers to allow it to swing down further or detach.
2. Access the Housing: Once the glove box is out of the way, you'll see a rectangular plastic housing with a clip or two. This is where the filter resides. Carefully unclip it and pull out the old filter.
3. Note Orientation: Pay close attention to the airflow direction arrow on the old filter. The new filter must be installed with the arrow pointing in the same direction (usually downwards, towards the floor of the car).
4. Install New Filter: Insert the new filter, ensuring it fits snugly without bending. Reattach the housing cover and reassemble the glove compartment.

Filter Type:

• Standard Filter: Good for trapping dust, pollen, and other airborne particles.
• Activated Charcoal Filter: These offer superior odor absorption, which would be beneficial for your musty smell issue. They are often a bit more expensive but worth it for improved air quality.

When to change:

• Mazda generally recommends changing the cabin air filter every 15,000 to 20,000 miles or once a year, whichever comes first. However, if you drive in dusty environments or notice odors, earlier replacement is advisable.

When to see a shop:

• If the musty smell persists after changing the filter, it might indicate mold or mildew buildup on the evaporator core, which requires a more involved cleaning process by a professional. There are no OBD codes associated with a dirty cabin air filter.