Maintenance procedure · Written to ASD-STE100 Issue 9 · Formatted to ANSI Z535

Replace a Cabin Air Filter

Passenger cars and light trucks — find the housing, record the arrow and the part number off the old filter, and fit the new one the right way round
ApplicabilityPassenger cars and light trucks with an owner-serviceable cabin air filter
Task time20 min to 40 min editorial estimate, not a measurement
PersonnelOne
Revisionv1 · 2026-07-29
BEFORE YOU BEGIN

Before you begin. This procedure is general reference information, not professional advice. Equipment varies by manufacturer, model, and year. Always follow the documentation supplied with your equipment — where it differs from this page, follow the manufacturer. Verify that you have the tools, the working conditions, and the ability to do this task safely. If anything is unclear, if the equipment is damaged, or if the task exceeds your experience, stop and use a qualified professional. You are responsible for your own safety and for the outcome. This site accepts no liability for any loss, damage, or injury arising from the use of this information.

Specifications marked unverified could not be traced to a manufacturer source. Do not rely on them — obtain the value from your equipment documentation.

Summary

A cabin air filter is the one that cleans the air coming into the car, and it is not the engine air filter. When it clogs, the first symptom is usually weak airflow from the vents with the blower on full, and the second is a musty smell. Toyota lists a clogged or extremely dirty cabin air filter as a common cause of no airflow from the car's air conditioning, and Mazda says the same thing from the other direction: if airflow drops significantly, the filter may be clogged. It is a fifteen-minute job on most cars and a dealer job on a few.

This page teaches you to find the housing rather than telling you where it is, because the location is genuinely model-specific — behind the glove box on many cars, under the scuttle or under the dash on others. It also will not print a part number or an airflow direction for your car. The direction matters: a cabin filter has an arrow printed on its frame, the arrow has to end up pointing the same way the old one did, and fitted backwards the filter can collapse and choke the very airflow you were trying to fix. The old filter in your hand is the authority for both, which is why this page has you read it before you throw it away.

Necessary equipment

ItemNote
FlashlightThe light below the instrument panel is low.
Vehicle documentationThe documentation gives the position of the filter for this vehicle.
Pen and paperRecord the part number and the direction of the arrow.
Plastic trim tool optionalUse a plastic tool to prevent damage to a clip.
Vacuum cleaner optionalUse the vacuum cleaner to remove leaves from the empty housing.
New cabin air filter materialThe new filter must be the same size as the used filter.
Plastic bag materialPut the used filter in a bag immediately.

Specifications

Replacement interval for the cabin air filter
Unverified — do not rely on this value
CONSULT THE MAINTENANCE SCHEDULE FOR THE VEHICLE

No tier-1 source was found for this value. Take it from the documentation supplied with your equipment.

Prepare the vehicle

Estimated 1 min

  1. Stop the vehicle in a safe place away from traffic.
    <1m
  2. Set the parking brake.
    <1m
WARNING

SET THE IGNITION TO OFF BEFORE YOU OPEN THE FILTER HOUSING.
The blower is behind the filter. The blower can start with no warning and injure your hand.

  1. Set the ignition to off.
    <1m
  2. Remove the key or the remote unit from the vehicle.
    <1m

Find the filter housing

Estimated 7 min to 19 min

NOTEThe position of the housing is different on each model.
Position of the filter housing
Unverified — do not rely on this value
CONSULT THE VEHICLE DOCUMENTATION

No tier-1 source was found for this value. Take it from the documentation supplied with your equipment.

  1. Read the vehicle documentation for the position of the cabin air filter.
    • Toyota tells owners that the position is different on each vehicle.
    • Many vehicles have the filter behind the glove box.
    • Some vehicles have the filter below the instrument panel or below the windshield.
    2m
  2. If the documentation gives no procedure for the owner, stop. Speak to a dealer for your make.
    • Mazda tells owners of some models to let an authorised dealer replace this filter.
    <1m
  3. Remove the contents of the glove box.
    1m
CAUTION

HOLD THE GLOVE BOX WHEN YOU RELEASE THE STOPS.
The glove box can fall on your hands.

  1. Release the stop at each side of the glove box.
    • The vehicle documentation shows the stops for your vehicle.
    • Some vehicles have a damper arm on one side. Release the arm first.
    2m
  2. Let the glove box move down.
    <1m
  3. Find the cover of the filter housing.
    • The cover is a rectangular panel behind the glove box.
    <1m
  4. Release the clips on the cover.
    • Use a plastic tool if a clip is tight.
    <1m
  5. Remove the cover.
    <1m

Record the filter before you remove it

Estimated 3 min to 7 min

NOTEThe used filter is the only reliable source for the size and the direction.
Cabin air filter part number
Unverified — do not rely on this value
READ THE PART NUMBER FROM THE FRAME OF THE USED FILTER, OR CONSULT THE VEHICLE DOCUMENTATION

No tier-1 source was found for this value. Take it from the documentation supplied with your equipment.

Cabin air filter size
Unverified — do not rely on this value
READ THE SIZE FROM THE FRAME OF THE USED FILTER

No tier-1 source was found for this value. Take it from the documentation supplied with your equipment.

Direction of the airflow arrow
Unverified — do not rely on this value
READ THE ARROW ON THE USED FILTER BEFORE YOU REMOVE IT. CONSULT THE VEHICLE DOCUMENTATION IF THE ARROW IS NOT LEGIBLE.

No tier-1 source was found for this value. Take it from the documentation supplied with your equipment.

  1. Find the arrow on the frame of the used filter.
    • The arrow shows the direction of the flow of air through the filter.
    • Some filters show the text AIR FLOW at the arrow.
    <1m
  2. Write down the direction of the arrow.
    • Make a mark on the housing in the same direction.
    • The direction is not the same on each vehicle.
    <1m
  3. Write down the size and the part number from the frame of the used filter.
    <1m
CAUTION

DIRT AND POLLEN FALL FROM A USED FILTER.
Keep the used filter away from your face. Put the used filter in a bag immediately.

  1. Remove the used filter from the housing.
    • Keep the used filter in a horizontal position.
    • Some housings need a small movement of the filter to release it.
    <1m
  2. Examine the used filter.
    • A used filter with leaves or with a nest is a sign of an open air inlet.
    • Toyota tells owners that a dirty filter decreases the flow of air.
    <1m
  3. Put the used filter in a bag.
    <1m

Install the new filter

Estimated 5 min to 9 min

NOTICE

USE ONLY A FILTER OF THE CORRECT SIZE FOR THE VEHICLE.
Air goes around a filter that is too small.

  1. Put the new filter beside the used filter.
    • Compare the length, the width and the depth.
    <1m
  2. If the two filters are not the same size, stop. Get the correct filter.
    <1m
NOTICE

PUT THE NEW FILTER IN THE SAME DIRECTION AS THE USED FILTER.
A filter in the wrong direction can collapse and decrease the flow of air.

  1. Clean the empty housing with a vacuum cleaner.
    1m
  2. Turn the new filter until its arrow points in the direction that you wrote down.
    <1m
  3. Put the new filter into the housing.
    • The filter must go fully into its guides.
    • Do not bend the frame of the filter.
    <1m
  4. Install the cover on the housing.
    • Engage each clip until you hear a sound.
    <1m
  5. Move the glove box up into its position.
    <1m
  6. Engage the stop at each side of the glove box.
    <1m

Do a check of the result

Estimated 3 min to 4 min

  1. Set the ignition to the on position.
    <1m
  2. Set the blower to its highest speed.
    <1m
  3. Listen for a new noise from the vents.
    • Toyota tells owners to listen for a new noise after this work.
    <1m
  4. Feel the flow of air at each vent.
    <1m
  5. Set the ignition to off.
    <1m
  6. Put the contents into the glove box again.
    1m
  7. Record the date, the part number, and the distance on the odometer.
    <1m

Terminology

This page uses one term for each item and holds it throughout, as ASD-STE100 requires. Equipment sellers and other guides use the names below for the same parts.

cabin air filter
Also called: pollen filter, AC filter, air conditioning filter, dust and pollen filter, interior air filter, car air filter behind the glove box
filter housing
Also called: filter box, filter tray, filter case, the slot the filter goes in
airflow arrow
Also called: AIR FLOW arrow, the arrow on the filter, which way does the arrow go, up or down arrow on cabin filter
glove box
Also called: glovebox, glove compartment, the box in front of the passenger
blower
Also called: blower motor, the fan, heater fan, AC fan

When to use a professional

Stop if the vehicle documentation gives no procedure for the owner. Speak to a dealer for your make.

Stop if the housing is not behind a cover that you can remove by hand. Some vehicles need the removal of a panel. Speak to a vehicle repair shop.

Stop if the air is cool but not cold. Stop if you hear a loud noise from the air conditioner. A filter does not correct these conditions. Speak to a vehicle repair shop.

Stop if water comes into the cabin at the filter. Speak to a vehicle repair shop.

Common questions

Where is the cabin air filter in my car?

Most often behind the glove box, but Toyota's own guidance is deliberately vague about it for a good reason: it can be in several places depending on the vehicle, and the owner's manual is the thing that knows. The other common locations are under the plastic scuttle panel at the base of the windscreen and under the dash on the passenger side. Look in the manual's index under cabin air filter, pollen filter or air conditioning filter — manufacturers do not agree on the name either.

My AC barely blows. Is it the filter?

It is the first thing to rule out. Toyota lists a clogged or extremely dirty cabin air filter as a common cause of no airflow from the car's air conditioning, and says it may restrict airflow from the vents dramatically. Mazda approaches it from the other side and tells owners that if the airflow of the climate control system decreases significantly, the filter may be clogged. If a new filter does not fix it, the next suspects are the blower motor and the ducting, and those are a workshop job.

Which way does the arrow go?

The same way it went on the filter you just took out — and that is the honest answer rather than a dodge. The arrow marks the direction of airflow through the filter, and airflow direction inside the housing is set by the car's design, so it points down on some vehicles and up or sideways on others. There is no universal answer and this page will not invent one. Look at the old filter, note the direction, and if the printing has worn away, get the direction from your manual before you fit anything.

What happens if I put it in backwards?

The pleated media is supported in one direction and not the other, so a filter fitted the wrong way round can be pushed out of shape by the blower and restrict the airflow it was meant to pass. That is the opposite of the outcome you were after, and it is easy to avoid: the whole reason this page has you read the old filter before you bin it is that the old filter is the only source for this that is guaranteed to be right for your car.

How often should it be changed?

Read your maintenance schedule, and then adjust for where you drive. Toyota's advice is to use the maintenance schedule or the owner's manual supplement for the interval, and notes that dusty areas or heavy traffic may mean replacing earlier than recommended. Mazda says the same: the filter may need replacing more frequently in areas with large amounts of dust and heavy traffic, such as large cities and cold regions. This page does not print an interval because there is no single right one.

Is the cabin filter the same as the engine air filter?

No, and mixing them up is the most common error in this job. The cabin air filter cleans the air that comes into the passenger compartment through the vents. The engine air filter cleans the air the engine draws in, and it lives in the engine compartment in its own box. They are different parts, different sizes and different part numbers, and replacing one does nothing for the symptoms of the other.

The car still smells musty with a new filter. Now what?

A new filter removes the smell that the old filter was holding, but not a smell that is growing somewhere else in the system. Damp in the ducting behind the filter, or a blocked drain letting water sit in the housing, will keep the smell coming back. Neither is something this page can walk you through safely. If a fresh filter does not clear it within a few days of driving, hand it to a workshop.

Sources

Every specification on this page is traced to one of these sources. Tier 1 is a manufacturer document, a published standard, or a government safety authority. See Standards for the full tiering rule.

  1. Tier 1Troubleshooting Common Car AC IssuesToyota Motor Sales, U.S.A., Inc. · accessed 2026-07-29 · re-verification due 2027-01-25
  2. Tier 1Air Conditioner Maintenance — 2025 Mazda3 Owner's ManualMazda North American Operations · accessed 2026-07-29 · re-verification due 2027-01-25

Revision history

Current version 1 · updated 2026-07-29 · next review due 2027-07-29

  1. v1 · 2026-07-29First draft. Built from Toyota's air conditioning troubleshooting guidance and Mazda's owner's manual section on air conditioner maintenance. No part number, size, airflow direction, housing location or replacement interval is printed: every one of them is per-vehicle and publishes as read-it-off-the-old-filter or consult-the-documentation. The airflow arrow is treated as the value with a consequence, and the record step that captures it comes before the step that removes the filter.

Corrections to this page are listed in the public corrections log. Reports that are credible and not yet verified are listed in the public errata register, and an open one renders above the step it concerns.

Comments and corrections

Found an error? A correction with a manufacturer source is applied and logged publicly. You can also write to corrections@fixchecklist.com.

Every step above carries its own report control, which tags the report with that step so a correction reaches the right place. For anything about the procedure as a whole — the order of the sections, a step that is missing, something that did not match your equipment — use this: report something about this whole procedure.

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