MB Medic Mercedes-Benz Repair Guides, Service, How To DIY
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In this guide (5 sections)
Replacing the cabin air filter on the Mercedes-Benz M-Class W163 is a relatively simple maintenance procedure that can usually be completed with basic hand tools. The cabin air filter is located in the interior of your SUV, on the passenger-side footwell. The job can typically be completed in about 5 to 15 minutes, depending on access and the condition of the trim and filter housing. Follow these easy step-by-step instructions on changing the cabin air filter. This procedure applies to the Mercedes-Benz M-Class W163, including the ML320, ML430, ML350, ML500, and ML55 AMG, built from 1998 to 2005. Filter specifications can vary by production number, so verify the correct filter for your vehicle before ordering. While many car owners forget to change the cabin air filter, inspect the cabin filter at regular service intervals and replace it when it becomes dirty, restricted, or develops an odor. Vehicles operated in dusty or polluted environments may require more frequent replacement.
The filter for the ML-Class W163 costs less than $20; see the link here to get one from Amazon. If you go to a mechanic or the dealer, you will be charged well over $100 for this 5-minute job.
Is the Filter Actually the Problem?
A clogged cabin filter is the first thing to check when the vents go quiet, but it does not explain every heating and air conditioning complaint on the W163.
- Weak airflow at every fan speed. This is the symptom the filter itself causes, and on a vehicle where nobody can remember the last change it is usually the whole answer. Air has to pass through the filter before it reaches any vent, so a blocked one chokes heating and cooling alike.
- Strong airflow, but the air is not cold. That is the refrigerant and compressor side of the system, not the filter, and a new filter will not change it. Start with recharging and checking the air conditioning on an ML instead.
- A musty smell that comes back within days of fitting a new filter. The filter was carrying the smell rather than creating it. Moisture sitting on the evaporator behind the dash will re-contaminate a clean filter quickly, so the filter is the symptom and not the cause.
Particle or Activated Charcoal?
Two kinds of filter fit this housing. A plain particle filter traps dust, pollen, and road grit. An activated charcoal filter does that and also absorbs odors and exhaust fumes drawn in from outside. If the complaint that brought you here is smell rather than dust, the charcoal type is the one worth paying for.
Tools and Parts Required
- Torx driver/socket as required for the lower dash fasteners
- Replacement cabin air filter
- Optional: vacuum cleaner for removing leaves and debris from the filter housing
Instructions: Changing the Cabin Air Filter
- Remove the fasteners securing the lower passenger-side dashboard/footwell cover, then lower the cover to access the cabin-filter housing.
- Release the retaining tab on the cabin filter access cover and remove the cover.
- Press on the locking tab and pull down the filter door cover.
- Pull down the interior cabin filter and note its orientation. If the replacement filter has an airflow-direction arrow, install it according to the arrow and the filter manufacturer’s instructions. Inspect the filter housing and remove loose leaves, dust, and debris before installing the new filter. Avoid pushing debris farther into the HVAC housing.
- Push the new air filter in place.
- Press the cabin air filter door into place.
- Reinstall the cover under the instrument panel.
- After installation, reinstall the trim panels and operate the HVAC blower. Confirm that airflow is normal and that there are no unusual noises from the blower.
Part Numbers
Note that the cabin air filter and the engine air filter are two different filters in two different places. If you are working through maintenance you have been putting off, the engine air filter on the W163 is a separate job. For what else this chassis is known for, see the common problems on the 1998 to 2005 ML.
Cabin Filter Part Number: A 163 835 00 47
Previous/replaced number: A 163 835 02 47
Mercedes-Benz used production/identification-number cutoffs for some W163 parts. Because the applicable filter can depend on production configuration, use the VIN or chassis/identification number to confirm the correct part.
Videos: Changing the Cabin Air Filter on an ML
Cabin Air Filter Mercedes ML320 W163
How to change the cabin air filter on an ML-Class
Before you buy parts, scan every control module, not just the engine. It shows the root fault behind the warning lights and tells you whether the problem is still active. See how to do a full health check.
